Understanding childhood, including the one you accompany

French health records changed charts in 2018. The debate turns on a technical distinction with very concrete consequences.

The idea of a window closing for good comes from animal ethology. In humans, the data support a far more flexible version.

Piaget placed around eight months the understanding that a hidden object still exists. Gaze-based methods moved that age, then were contested.

Around age two, a child starts treating a stick as a telephone. That conduct is a solid marker; what it produces is far less established.

The order in which a child sits, crawls and then walks is remarkably constant. The ages at which they do so vary far more than is usually said.

Counting hours puts a video call and a looping video in the same box. The most recent work shows this variable explains very little.

A child who waits fifteen minutes in front of a sweet was said to become a better-off adult. The 2018 replication greatly shrank that statement, without cancelling it.

A simple test, in use since 1983, seemed to place around age four the ability to attribute a mistaken belief to someone else. Non-verbal versions have blurred that timetable.

A laboratory procedure devised in 1969 still supplies most of the data on attachment. It measures something real, and far narrower than is often claimed.

A child who says nothing may understand a great deal. The gap between what is understood and what is produced is one of the best established facts about language development.

Charts stating how many hours a six-month-old sleeps do exist. What they hide is how widely children scatter around the average.