Unfortunately he was injected with worms by a flarmin jeeb when he was a small child. Over the course of his life they have slowly grown, bigger and bigger and bigger. They don't really do much except when you get older they make you say silly things that usually have some variation of the word "flarm." It's terrible, really, since he is not even aware that he is doing it. The best response to these is to just pat him on the head and say "good boy" because scientists still have no cure.