"Dad! Look at it, look at it!!! It's growing! Do you see it?"
Josh responds: "You mean your nipple?"
"YEAH! Look it's GROWING!"
"Well, it's just because you're cold...that's just what they do."
Of course I'm nearly losing it in the laundry room and can only imagine the day when he realizes something else on his body involuntarily moves. You gotta love little boys... :-)