My mother relayed this little conversation gem from her day with the kids:
Scene: the kids are splashing around in the tub together...
Mr.Moo: Grandma! Boudica doesn't have a pee-er! Why, grandma? Where is it? I can't see it!
Grandma: It's ok, she has one. Don't worry.
Mr.Moo: Grandma! Grandma! Where is Boudica's pee-er?!? Where? I want to see it.
Grandma (squirming): Don't worry about it, honey.
Mr. Moo (insisting): But Grandma, where is her pee-er? I can't see it!
My mother finally realized that she was not getting out of this one easily, so as she took Boudica out of the tub, she casually gestured in the general direction of her crotch and said, "See? It's just flat, that's all." I expect his next inquiry to be along the lines of asking (incessantly, of course) what squashed Boudica's pee-er, and why is it flat. This kid. He is the elephant.