
Ages
Three seasons, not a race
Children do not switch bands on a birthday. If you are between seasons, read both. Then open a post for the problem that is actually in the house.

Motion and pointing
First steps, first words, safer floors.

Words and will
Two-word phrases start. So do harder no's.

Conversation and play
Pretend play, potty readiness, and a one-hour media ceiling.
After you pick a season, the next step is guides for common questions.