If he is 3 yrs. old and NOT complaining about it, then I would just watch it...or ask him.
If it is red and looks unhealthy or perhaps looks uneven in color, then I would call the doctor just so s/he can do a looksee.
both of my sons are circumsized...but one can never not know too much about uncircumsized penises. I have heard it is an unnecessary procedure and being uncircumsized is rather beneficial in adult life.
[[coughs discreetly]]
