Baby development milestones 0–5 years (as release notes)

v5.0.0 – Milestones by 5 years: Ready for school

Counts to 10, writes some letters of their name and hops on one foot. Long-term support begins.

✨ Added – CDC: what most children do by 5 years

💛 Social/Emotional

• Follows rules or takes turns in games with other children
• Sings, dances, or acts for you
• Does simple chores, like matching socks or clearing the table

💬 Language/Communication

• Tells a story with at least two events
• Answers simple questions about a book or story
• Keeps a conversation going with more than three back-and-forth exchanges
• Uses or recognizes simple rhymes (bat–cat, ball–tall)

🧠 Cognitive

• Counts to 10
• Names some numbers between 1 and 5 when you point to them
• Uses words about time, like “yesterday”, “tomorrow”, “morning”
• Pays attention for 5 to 10 minutes during activities (screen time doesn’t count)
• Writes some letters of their name
• Names some letters when you point to them

🏃 Movement/Physical

• Buttons some buttons
• Hops on one foot

Source: CDC, Learn the Signs. Act Early. – 5 years (lightly paraphrased).

v4.0.0 – Milestones by 4 years: Imagination engine

Pretend play, four-word sentences and a strong interest in being the helper.

✨ Added – CDC: what most children do by 4 years

💛 Social/Emotional

• Pretends to be something else during play (teacher, superhero, dog)
• Asks to go play with children if none are around
• Comforts others who are hurt or sad
• Avoids danger, like not jumping from tall heights
• Likes to be a “helper”
• Changes behavior based on the place (library, playground)

💬 Language/Communication

• Says sentences with four or more words
• Says some words from a song, story, or nursery rhyme
• Talks about at least one thing that happened during the day
• Answers simple questions like “What is a coat for?”

🧠 Cognitive

• Names a few colors
• Tells what comes next in a well-known story
• Draws a person with three or more body parts

🏃 Movement/Physical

• Catches a large ball most of the time
• Serves food or pours water, with adult supervision
• Unbuttons some buttons
• Holds a crayon or pencil between fingers and thumb (not a fist)

🐛 Known issues (all normal)

• Lots of “why” questions. CDC suggests taking time to answer them, and it’s fine to say “I don’t know”. [source]

💡 Tips

• Tantrums become much less common by about age 4, as children can put more of their feelings into words; naming feelings for them (“I know you’re angry because…”) helps. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 4 years (lightly paraphrased).

v3.0.0 – Milestones by 3 years: Conversation protocol

Supports back-and-forth conversation and the full who/what/where/why query set.

✨ Added – CDC: what most children do by 3 years

💛 Social/Emotional

• Calms down within 10 minutes after you leave, like at childcare drop-off
• Notices other children and joins them to play

💬 Language/Communication

• Has conversations with at least two back-and-forth exchanges
• Asks “who”, “what”, “where”, or “why” questions
• Says what action is happening in a picture or book
• Says their first name when asked
• Talks well enough for others to understand, most of the time

🧠 Cognitive

• Draws a circle when shown how
• Avoids touching hot objects, like a stove, when warned

🏃 Movement/Physical

• Strings items together, like large beads or macaroni
• Puts on some clothes by themselves
• Uses a fork

💡 Tips

• Once walking, young children benefit from at least 3 hours of physical activity a day, spread across the day – parks, walking instead of the buggy and helping with chores all count. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 3 years (lightly paraphrased).

v2.6.0 – Milestones by 30 months: Pronoun support

Adds “I”, “me” and “we”. Vocabulary around 50 words. Jumping with both feet.

✨ Added – CDC: what most children do by 30 months

💛 Social/Emotional

• Plays next to other children and sometimes with them
• Shows you what they can do by saying “Look at me!”
• Follows simple routines when told, like clean-up time

💬 Language/Communication

• Says about 50 words
• Says two or more words together, with one action word, like “Doggie run”
• Names things in a book when you point and ask
• Says words like “I”, “me”, or “we”

🧠 Cognitive

• Uses things to pretend, like feeding a block to a doll
• Shows simple problem-solving, like standing on a stool to reach something
• Follows two-step instructions
• Shows they know at least one color

🏃 Movement/Physical

• Uses hands to twist things, like doorknobs or lids
• Takes some clothes off by themselves
• Jumps off the ground with both feet
• Turns book pages one at a time

🐛 Known issues (all normal)

• Toilet training: most children are not able to toilet train until 2 to 3 years old; starting too early can cause setbacks. [source]

💡 Tips

• Reply with a sentence a few words longer than your child’s (“sock off” → “yes, we’re taking your sock off”), and switch off background TV or radio so they can hear you. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 30 months (lightly paraphrased).

v2.0.0 – Milestones by 2 years: Two-word queries

Breaking change: commands now accept two arguments (“More milk”). Running is enabled.

✨ Added – CDC: what most children do by 2 years

💛 Social/Emotional

• Notices when others are hurt or upset
• Looks at your face to see how to react in a new situation

💬 Language/Communication

• Points to things in a book when asked, like “Where is the bear?”
• Says at least two words together, like “More milk”
• Points to at least two body parts when asked
• Uses more gestures than waving and pointing, like blowing a kiss or nodding yes

🧠 Cognitive

• Holds something in one hand while using the other, like opening a container
• Tries to use switches, knobs, or buttons on a toy
• Plays with more than one toy at the same time, like toy food on a toy plate

🏃 Movement/Physical

• Kicks a ball
• Runs
• Walks (not climbs) up a few stairs, with or without help
• Eats with a spoon

🐛 Known issues (all normal)

• Children this age play next to each other but don’t yet know how to share or solve conflicts. [source]
• Appetite varies: toddlers don’t always eat the same amount or type of food each day. [source]

💡 Tips

• Short, simple instructions (“Get your coat”) are easiest to follow, and repeating words in different sentences helps them stick. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 2 years (lightly paraphrased).

v1.6.0 – Milestones by 18 months: Autonomous mode

Walks unassisted, climbs furniture and explores away from you — while pinging home to check you’re still there.

✨ Added – CDC: what most children do by 18 months

💛 Social/Emotional

• Moves away from you, but looks to make sure you are close by
• Points to show you something interesting
• Puts hands out for you to wash them
• Looks at a few pages in a book with you
• Helps you dress them by pushing an arm through a sleeve or lifting a foot

💬 Language/Communication

• Tries to say three or more words besides “mama” or “dada”
• Follows one-step directions without gestures, like “Give it to me”

🧠 Cognitive

• Copies you doing chores, like sweeping
• Plays with toys in a simple way, like pushing a toy car

🏃 Movement/Physical

• Walks without holding on to anyone or anything
• Scribbles
• Drinks from an open cup, sometimes spilling
• Feeds themselves with fingers
• Tries to use a spoon
• Climbs on and off a couch or chair without help

🐛 Known issues (all normal)

• Tantrums are still normal and should become shorter and less frequent over time. [source]
• Toilet training: most children are not successful until 2 to 3 years old. Ask your child’s doctor about readiness. [source]

💡 Tips

• Tantrums often begin around 18 months, partly from frustration at not yet being able to say what they want. Spotting tiredness or hunger, or a quick distraction, can help. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 18 months (lightly paraphrased).

v1.3.0 – Milestones by 15 months: Walking (beta)

First steps without a handrail. Vocabulary API expanded beyond “mama” and “dada”.

✨ Added – CDC: what most children do by 15 months

💛 Social/Emotional

• Copies other children while playing
• Shows you an object they like
• Claps when excited
• Hugs a stuffed doll or other toy
• Shows you affection (hugs, cuddles, or kisses)

💬 Language/Communication

• Tries to say one or two words besides “mama” or “dada”, like “ba” for ball
• Looks at a familiar object when you name it
• Follows directions given with both a gesture and words
• Points to ask for something or to get help

🧠 Cognitive

• Tries to use things the right way, like a phone, cup, or book
• Stacks at least two small objects, like blocks

🏃 Movement/Physical

• Takes a few steps on their own
• Uses fingers to feed themselves some food

📊 Typical windows (WHO)

• Walking alone: usually between 8.2–17.6 months

Range = 1st to 99th percentile of healthy children in the WHO Motor Development Study.

🐛 Known issues (all normal)

• Tantrums: CDC calls them normal at this age, more likely when tired or hungry, and says they should get shorter and less frequent with age. [source]
• Early words are not complete (“ba” for ball). Repeating the full word back helps. [source]

💡 Tips

• If a word comes out wrong, simply say it back correctly (“Yes, it’s a cat”) without correcting or criticising. Offering choices (“apple or banana?”) builds vocabulary. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 15 months (lightly paraphrased).

v1.0.0 – Month 12 milestones (11–12 months): First stable release

End of year one: pulls up to stand, walks holding on to furniture and calls you “mama”, “dada” or another special name.

✨ Added – CDC: what most children do by 12 months

💛 Social/Emotional

• Plays games with you, like pat-a-cake

💬 Language/Communication

• Waves “bye-bye”
• Calls a parent “mama”, “dada”, or another special name
• Understands “no” (pauses briefly or stops)

🧠 Cognitive

• Puts something in a container, like a block in a cup
• Looks for things they saw you hide, like a toy under a blanket

🏃 Movement/Physical

• Pulls up to stand
• Walks while holding on to furniture
• Drinks from an open cup while you hold it
• Picks things up between thumb and pointer finger

📊 WHO motor windows at 11–12 months

• Hands-and-knees crawling: 5.2–13.5 months (open)
• Standing with assistance: 4.8–11.4 months (closes this month – 99th percentile reached)
• Walking with assistance: 5.9–13.7 months (open)
• Standing alone: 6.9–16.9 months (open)
• Walking alone: 8.2–17.6 months (open)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

🐛 Known issues (all normal)

• New foods may be rejected on the first try. CDC suggests offering them again and again. [source]

💡 Tips

• Look after yourself, physically and emotionally. Parenting is hard work, and it is easier to be a loving parent when you feel good too. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Keep breastfeeding or giving first infant formula until at least 1 year; pasteurised whole or semi-skimmed cows’ milk can become a main drink from 12 months. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 12 months (lightly paraphrased).

v0.11.0 – Month 11 milestones (10–11 months): Patch: pre-release

No CDC checklist this month. One more patch before the 12-month checklist.

✨ Added

No CDC milestone checklist exists for this month (CDC publishes checklists for 2, 4, 6, 9 and 12 months), so no milestones are listed here on purpose.

📊 WHO motor windows at 10–11 months

• Hands-and-knees crawling: 5.2–13.5 months (open)
• Standing with assistance: 4.8–11.4 months (open)
• Walking with assistance: 5.9–13.7 months (open)
• Standing alone: 6.9–16.9 months (open)
• Walking alone: 8.2–17.6 months (open)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

💡 Tips

• Sing to your baby and play music; CDC says it supports brain development. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Books don’t need to be read word for word yet – just talk about the pictures together. – Contains public sector information licensed under the Open Government Licence v3.0.

v0.10.0 – Month 10 milestones (9–10 months): Patch: first window closes

No CDC checklist this month. The WHO window for sitting without support closes (99th percentile).

✨ Added

No CDC milestone checklist exists for this month (CDC publishes checklists for 2, 4, 6, 9 and 12 months), so no milestones are listed here on purpose.

📊 WHO motor windows at 9–10 months

• Sitting without support: 3.8–9.2 months (closes this month – 99th percentile reached)
• Hands-and-knees crawling: 5.2–13.5 months (open)
• Standing with assistance: 4.8–11.4 months (open)
• Walking with assistance: 5.9–13.7 months (open)
• Standing alone: 6.9–16.9 months (open)
• Walking alone: 8.2–17.6 months (open)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

💡 Tips

• Read to your baby – it helps them understand language and sounds. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Turn-taking games such as peek-a-boo practise attention, listening and taking turns. – Contains public sector information licensed under the Open Government Licence v3.0.

v0.9.0 – Month 9 milestones (8–9 months): Object permanence

Things that leave the screen no longer cease to exist. Stranger detection enabled by default.

✨ Added – CDC: what most children do by 9 months

💛 Social/Emotional

• Is shy, clingy, or fearful around strangers
• Shows several facial expressions (happy, sad, angry, surprised)
• Looks when you call their name
• Reacts when you leave (looks, reaches for you, or cries)
• Smiles or laughs at peek-a-boo

💬 Language/Communication

• Makes lots of different sounds like “mamamama” and “bababababa”
• Lifts arms up to be picked up

🧠 Cognitive

• Looks for objects dropped out of sight (like a spoon or toy)
• Bangs two things together

🏃 Movement/Physical

• Gets to a sitting position by themselves
• Moves things from one hand to the other
• Uses fingers to “rake” food towards themselves
• Sits without support

📊 WHO motor windows at 8–9 months

• Sitting without support: 3.8–9.2 months (open)
• Hands-and-knees crawling: 5.2–13.5 months (open)
• Standing with assistance: 4.8–11.4 months (open)
• Walking with assistance: 5.9–13.7 months (open)
• Standing alone: 6.9–16.9 months (open)
• Walking alone: 8.2–17.6 months (opens this month)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

🐛 Known issues (all normal)

• Shyness or clinginess around strangers is listed by CDC as an expected milestone at this age, not a bug. [source]
• Dropping things over and over is a game. Handing it back helps them learn. [source]
• Not every child crawls on hands and knees: in the WHO study, 4.3% of children never did. [source]

💡 Tips

• Once your baby is on the move and grabbing things they shouldn’t, redirect with a toy or move them somewhere safe. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Name and point to things you both see (“Look, a dog!”), then add detail as your baby grows (“a big brown dog”). – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 9 months (lightly paraphrased).

v0.8.0 – Month 8 milestones (7–8 months): Patch: window update

No CDC checklist this month. Every WHO window except walking alone is now open.

✨ Added

No CDC milestone checklist exists for this month (CDC publishes checklists for 2, 4, 6, 9 and 12 months), so no milestones are listed here on purpose.

📊 WHO motor windows at 7–8 months

• Sitting without support: 3.8–9.2 months (open)
• Hands-and-knees crawling: 5.2–13.5 months (open)
• Standing with assistance: 4.8–11.4 months (open)
• Walking with assistance: 5.9–13.7 months (open)
• Standing alone: 6.9–16.9 months (open)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

💡 Tips

• Cut food into small bites and keep small toys and other easy-to-swallow things away to prevent choking. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Teething varies a lot: many babies get a first tooth at around 6 months, but some start before 4 months and others after 12. A chilled (never frozen) teething ring can help; never tie one around the neck. – Contains public sector information licensed under the Open Government Licence v3.0.

v0.7.0 – Month 7 milestones (6–7 months): Patch: standing update

No CDC checklist this month. The WHO window for standing alone opens.

✨ Added

No CDC milestone checklist exists for this month (CDC publishes checklists for 2, 4, 6, 9 and 12 months), so no milestones are listed here on purpose.

📊 WHO motor windows at 6–7 months

• Sitting without support: 3.8–9.2 months (open)
• Hands-and-knees crawling: 5.2–13.5 months (open)
• Standing with assistance: 4.8–11.4 months (open)
• Walking with assistance: 5.9–13.7 months (open)
• Standing alone: 6.9–16.9 months (opens this month)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

🥄 Feeding facts

There is no reason to introduce potentially allergenic foods (egg, cereals, fish, peanut) later than other complementary foods, as far as allergy risk is concerned; gluten can be introduced along with other foods.

Source: EFSA NDA Panel (2019). Scientific opinion on the appropriate age range for introduction of complementary feeding into an infant’s diet. EFSA Journal 17(9):5780. doi:10.2903/j.efsa.2019.5780

💡 Tips

• Feed slowly and patiently. Offer new tastes without forcing, and watch for signs your baby is still hungry or full. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• From around 6 months you can offer sips of water from an open or free-flow cup (no valve) with meals – it helps babies learn to sip. – Contains public sector information licensed under the Open Government Licence v3.0.

v0.6.0 – Month 6 milestones (5–6 months): Laughter shipped

Full laugh support lands. Everything is now tested by putting it in the mouth.

✨ Added – CDC: what most children do by 6 months

💛 Social/Emotional

• Knows familiar people
• Likes to look at self in a mirror
• Laughs

💬 Language/Communication

• Takes turns making sounds with you
• Blows “raspberries” (sticks tongue out and blows)
• Makes squealing noises

🧠 Cognitive

• Puts things in mouth to explore them
• Reaches to grab a toy they want
• Closes lips to show they don’t want more food

🏃 Movement/Physical

• Rolls from tummy to back
• Pushes up with straight arms when on tummy
• Leans on hands to support themselves when sitting

📊 WHO motor windows at 5–6 months

• Sitting without support: 3.8–9.2 months (open)
• Hands-and-knees crawling: 5.2–13.5 months (opens this month)
• Standing with assistance: 4.8–11.4 months (open)
• Walking with assistance: 5.9–13.7 months (opens this month)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

🥄 Feeding facts

For nutritional reasons, most infants need complementary foods from around 6 months. Some infants at risk of low iron stores may benefit from iron-containing foods earlier.

Source: EFSA NDA Panel (2019). Scientific opinion on the appropriate age range for introduction of complementary feeding into an infant’s diet. EFSA Journal 17(9):5780. doi:10.2903/j.efsa.2019.5780

💡 Tips

• CDC says breast milk covers a baby’s needs for about the first 6 months; between 6 and 12 months, healthy solid foods bring new tastes and textures while breast milk stays important. Ask your paediatrician when to start. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Readiness for first solid foods usually shows from around 6 months as three signs together: sitting up with a steady head, getting food to the mouth with eyes and hands working together, and swallowing food instead of pushing it back out. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 6 months (lightly paraphrased).

v0.5.0 – Month 5 milestones (4–5 months): Patch: new windows

No CDC checklist this month. More WHO motor windows open – windows, not deadlines.

✨ Added

No CDC milestone checklist exists for this month (CDC publishes checklists for 2, 4, 6, 9 and 12 months), so no milestones are listed here on purpose.

📊 WHO motor windows at 4–5 months

• Sitting without support: 3.8–9.2 months (open)
• Standing with assistance: 4.8–11.4 months (opens this month)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

🥄 Feeding facts

Skills for eating finger foods appear in some infants at 4 months, but more commonly between 5 and 7 months. Being developmentally ready before 6 months does not by itself mean complementary food is needed.

Source: EFSA NDA Panel (2019). Scientific opinion on the appropriate age range for introduction of complementary feeding into an infant’s diet. EFSA Journal 17(9):5780. doi:10.2903/j.efsa.2019.5780

💡 Tips

• Play when your baby is alert and relaxed, and take a break when they look tired or fussy. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Singing to your baby helps them tune in to the rhythm of language. – Contains public sector information licensed under the Open Government Licence v3.0.

v0.4.0 – Month 4 milestones (3–4 months): Audio output: cooing

Two-way audio is in beta. Smiles are now sent proactively instead of only on request.

✨ Added – CDC: what most children do by 4 months

💛 Social/Emotional

• Smiles on their own to get your attention
• Chuckles (not yet a full laugh) when you try to make them laugh
• Looks at you, moves, or makes sounds to get or keep your attention

💬 Language/Communication

• Makes cooing sounds like “oooo” and “aahh”
• Makes sounds back when you talk to them
• Turns head towards the sound of your voice

🧠 Cognitive

• If hungry, opens mouth on seeing breast or bottle
• Looks at their hands with interest

🏃 Movement/Physical

• Holds head steady without support when held
• Holds a toy when you put it in their hand
• Swings an arm at toys
• Brings hands to mouth
• Pushes up onto elbows/forearms when on tummy

📊 WHO motor windows at 3–4 months

• Sitting without support: 3.8–9.2 months (opens this month)

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

🐛 Known issues (all normal)

• Putting safe things in the mouth is how babies explore and learn. Only let them mouth things that are not sharp, hot, or small enough to choke on. [source]

🥄 Feeding facts

The earliest developmental skills needed to eat puréed food can be seen between 3 and 4 months of age.

Source: EFSA NDA Panel (2019). Scientific opinion on the appropriate age range for introduction of complementary feeding into an infant’s diet. EFSA Journal 17(9):5780. doi:10.2903/j.efsa.2019.5780

💡 Tips

• Floor time counts: moving around on the floor helps babies get strong and explore. Try not to leave them in swings, bouncers or strollers for long stretches. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• From around 4 months, place toys close by so your baby can try to reach for them, and look at baby books together. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 4 months (lightly paraphrased).

v0.3.0 – Month 3 milestones (2–3 months): Maintenance release

No CDC checklist this month; no WHO motor windows open yet.

✨ Added

No CDC milestone checklist exists for this month (CDC publishes checklists for 2, 4, 6, 9 and 12 months), so no milestones are listed here on purpose.

📊 WHO motor windows at 2–3 months

No WHO window is open yet – the earliest (sitting without support) opens at 3.8 months.

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

💡 Tips

• When your baby makes a sound, repeat it back and add a word or two. It helps them learn language. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• A lively, sing-song tone of voice helps hold a young baby’s attention when you talk to them. – Contains public sector information licensed under the Open Government Licence v3.0.

v0.2.0 – Month 2 milestones (1–2 months): Hello, world

First public build. Mostly runs on milk and sleep, but the UI is starting to respond to input.

✨ Added – CDC: what most children do by 2 months

💛 Social/Emotional

• Calms down when spoken to or picked up
• Looks at your face
• Seems happy to see you when you walk up
• Smiles when you talk to or smile at them

💬 Language/Communication

• Makes sounds other than crying
• Reacts to loud sounds

🧠 Cognitive

• Watches you as you move
• Looks at a toy for several seconds

🏃 Movement/Physical

• Holds head up when on tummy
• Moves both arms and both legs
• Opens hands briefly

📊 WHO motor windows at 1–2 months

No WHO window is open yet – the earliest (sitting without support) opens at 3.8 months.

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

🐛 Known issues (all normal)

• Crying is often worse in the first few months of life, but it gets better. Never shake a baby. If you get upset when they cry, put the baby in a safe place, walk away, and check on them every 5–10 minutes. [source]

💡 Tips

• Talk to your baby a lot; CDC notes that babies find a parent’s voice calming. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Narrate everyday care: describe what you are doing while you feed, change or bath your baby. – Contains public sector information licensed under the Open Government Licence v3.0.

Source: CDC, Learn the Signs. Act Early. – 2 months (lightly paraphrased).

v0.1.0 – Month 1 milestones (0–1 months): Initial commit

Newborn firmware boots. No CDC checklist for month 1 and no WHO motor windows open yet.

✨ Added

No CDC milestone checklist exists for this month (CDC publishes checklists for 2, 4, 6, 9 and 12 months), so no milestones are listed here on purpose.

📊 WHO motor windows at 0–1 months

No WHO window is open yet – the earliest (sitting without support) opens at 3.8 months.

Window = 1st to 99th percentile of age at achievement among healthy children in the WHO Motor Development Study (WHO MGRS 2006, PDF). Windows are wide and overlap; they are not deadlines.

💡 Tips

• Put your baby down to sleep on their back every time – CDC recommends this to lower the risk of SIDS. – based on CDC, Positive Parenting Tips: Infants (0–1 years), rewritten.
• Hold your baby close and look at them while you talk – babies are drawn to faces and will watch you and react. – Contains public sector information licensed under the Open Government Licence v3.0.