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Birth through age 25

Know the stage. Nail the moment.

What is developmentally true at every age, in plain language, with what your grandchild needs from you at each step.

Six stages, 237 month-by-month developmental notes and 312 things to do together, covering birth through age 25.

Most developmental information is written for parents, who are watching it happen up close and every day. This is written for grandparents, who are watching from one generation back and often from a distance, and who need something different from it: not a checklist to monitor, but a way to know what is going on for this child right now so that a phone call, a visit, or a gift actually lands.

Two things are true throughout. Milestones are ranges, not deadlines. Two children can reach the same one eight months apart and both be entirely on track. And development is not a ladder a child climbs alone; it is a set of things they are working on, which is why every stage below says what a grandchild needs from you as well as what they can do.

Pick the stage your grandchild is in. Read the one below it and the one above it too, because children rarely sit neatly inside a band.

Birth to 12 months

Baby

What can my newborn grandbaby actually see and do?

22 developmental notes · 12 Gran Dates

Open baby →
1 to 3 years

Toddler

Why does my toddler grandchild say no to everything?

24 developmental notes · 24 Gran Dates

Open toddler →
3 to 5 years

Preschool

What is my preschool grandchild working on?

24 developmental notes · 24 Gran Dates

Open preschool →
5 to 11 years

School Age

How do I stay close to a school-age grandchild?

77 developmental notes · 77 Gran Dates

Open school age →
11 to 18 years

Teen

My teenage grandchild has gone quiet. Is that normal?

90 developmental notes · 91 Gran Dates

Open teen →
18 to 25 years

Young Adult

What is my role once my grandchild is an adult?

84 Gran Dates

Open young adult →

Milestones are ranges, not deadlines. Everything here describes what is developmentally typical, and two children can reach the same milestone many months apart and both be entirely on track. Nothing on this page is a diagnosis, a screening tool, or medical advice. If you have a concern about a child, that conversation belongs with the child's parents and the child's pediatrician.

Which grandparent are you becoming?

Five minutes, fifteen questions, and guidance matched to your result rather than to grandparents in general.

Last updated August 20, 2026. Reviewed for accuracy against current developmental guidance.