I walked yesterday with my son (5 years old) on a large common playground. Lots of people, hills, plugs, snow and so on. It fits to my shirt approximately the same age:

Hello to you! Let’s play hiding?

Hi, let me go.

Count to 20 and start searching.

I stand and watch. The son counted and ran to look for it. In a few minutes I see that he is already doing other things, I approach and ask:

Have you found the boy?

and no.

Why are you not looking?

I forgot how he looks.