Peanut butter is really high in fat, so yes it can cause diarrhea. Also over feeding your pup can cause it. If I remember right you just got George, and he is a young puppy? I wouldn't be putting more than a teaspoon of peanut butter in his Kong. If you freeze the pb stuffed kong it will last a bit longer.
Pam, Mom to
Thor-male brindle 05/24/01
Arabella-female brindle 12/19/06
Star-at the bridge 05/13/98-11/22/08