Eye rubbing

Why do kids rub their eyes when they are tired? All kids seem to do it, yet I can’t believe that it is a learned behavior.

Well, when i get tired,sleepy, my eyes burn,itch,are irritated. so i rub them. just natural. even animals do it. In fact I DID learn a good way from m dog but you gotta get on the floor ,put you knee up by your shoulder, aw forget it ,it’s way complicated.

“Pardon me while I have a strange interlude.”-Marx

…knee by my shoulder and foot behind my head?