Week by Week

Everything below is written for breastfeeding.

Months 36–47 · one-glance sheet

Year 3

Full sentences, endless questions, and real friendships starting to form. Most of what's 'baby' about them is gone now.

1
The 3-year checkup
Includes vision, hearing, and a fuller developmental and behavioral screen.
2
Preschool or structured group time, if it's an option
Not required for development, but a common and useful step for social skills this year.
3
Car seat stage, not age
Forward-facing with harness until they outgrow the seat's height or weight limit — usually well past 3.

your call

if still going

3 + 2

meals + snacks

no deadline

for stopping

Uncommon at this age in some cultures, entirely typical in others — it carries no risk and no expiration date.

Draft figures for this age, pending clinical review.

Trust the worry. None of this is an overreaction.

Speech that's still hard for unfamiliar adults to understand by age 4.
No interest in interactive or pretend play, or in other children, by age 3.
Loss of a skill they used to have — language, movement, or social — at any age.
Frequent, extreme tantrums well past age 4, or any self-injury during them.
Vision or hearing concerns flagged at the 3-year checkup that haven't been followed up on.

If you want the detail

Drafted from public sources — see the full source list. This is not medical advice — call your pediatrician with any concern.