We have a 9 week old kitten. When he's tired he likes to try and nurse on the (male) dog. Cat will find one of his nipples and get stuck in. The dog pulls a funny face but doesn't seem to mind too much. He was even licking the kitten while he was doing it earlier.
It's really cute, but I don't know if I should stop the kitten from doing it. I've been distracting him with some food, but I don't want to over feed him lol.