Marry Grandma

"Daddy," said a six-year-old boy, "I'd like to get married."

"Sure, son." said his father. "Anyone special in mind?"

"Yes," answered the boy. "Grandma. Shes nice."

"Now, wait a minute," said his father. "You don't think I'd let you marry my mother, do you!"

"Why not?" the boy asked. "You married mine."