Looks for objects that are hidden

What is this milestone?

Understands objects exist even when hidden

Object permanence is the cognitive understanding that objects (and people) continue to exist even when they cannot be seen, heard, or felt. If you hide a toy under a blanket, they will actively search for it.

Why it matters

This is a profound shift in how your baby perceives reality. It’s the foundation for memory, abstract thinking, and problem-solving. It also explains why separation anxiety often begins around this time, as they know you exist when you leave the room.

What to expect leading up to it

Before grasping this concept, if a toy is hidden, a baby will simply lose interest as if it vanished. As this skill develops, you'll notice them staring at the spot where an object disappeared or trying to move an obstacle to find it.

How to encourage and support it

Play plenty of peek-a-boo! You can also hide a favorite toy partially under a towel, encouraging them to pull it away. Gradually make the hiding spots slightly more challenging to gently stretch their newfound cognitive abilities.

When to talk to your doctor

This one develops gradually and is hard to pin to a date, so there is no single cut-off to watch. Mention it to your pediatrician if by around 12 months your baby shows no interest in looking for things that disappear, does not follow your gaze, or seems generally uninterested in the people and objects around them. And at any age, if your baby loses a skill they already had, tell your pediatrician that week.