Toilet humor is a metaphor for something that is x-rated, obscene, or truly rude. In this case, it is anything but.
In fact, this is one of the cuter jokes I have found in a while.
So let your inner 3 year out out and smile with me on this one.
Another bathroom joke
A little four-year-old boy is in the bathroom.
His mother thinks he has been in there too long, so she goes in to see what’s up.
“Matty, are you all right?” she says. “You’ve been in here for a while…”
Matty says, “I’m fine, Mommy… I just haven’t gone ‘doody’ yet.”
The little boy is sitting on the toilet impatiently. Every ten seconds or so he grips the toilet seat with his left hand and hits himself on top of the head with his right hand.
“Matty, why are you hitting yourself on the head?” his mother asks, concerned. Matty responds, “Works for ketchup.”