Tickle Foot

My son has become interested in tickling feet. He calls it 'tickle foot'. Today they were playing house. He was the daddy and his younger sister, Child2, was the mommy. He began to tickle foot her. She got angry.

"Stop tickle footing me!"

"Why? It's fun," he says.

"Daddies do not tickle foot mommies."

"Yes, they do."

"They do not," she says, "Have you seen Daddy do this to Mommy?"

"Yes," he replies, "I saw Daddy do this to Mommy. So, daddies do tickle foot mommies. I was right and you were wrong."