Jimmy's mother moves out of her house and into an apartment, and calls to say she can no longer keep his childhood dog, Happy. Jimmy wants to take the dog, but can't because Greg's allergic. After Kim tries to convince Greg to take it in anyway, Greg tells the truth -- he's not allergic to dogs, he just doesn't like them. Kim ignores Greg's wishes, and lets Jimmy and Christine keep Happy there. To get even with her, Greg gets something Kim doesn't want around: a go-cart. Happy arrives, but is hardly the dog Jimmy remembers; he's more like Cujo. Kim admits to Greg that she made a mistake, but still doesn't want to tell Jimmy to get rid of it -- even though Christine agrees it needs to go. Happy gets loose and chases after Greg while riding his go-cart, causing him to have an accident. But it's not Greg who gets hurt. While at the vet's, Greg, Kim and Christine are finally able to convince Jimmy that Happy is too aggressive to keep. The vet tells Jimmy that Happy is a goner and should be

The Warners and the Hughes invite the neighbors, Rob and Wendy, and their kids over. Greg decides to join a gym after seeing Rob give rocket ship rides to Sam, because he's too exhausted to give them to Sam himself. But Greg has no idea what to do at the gym and contemplates hiring a personal trainer, which Jimmy thinks is a waste of money. So he volunteers to personally train Greg himself. Christine, meanwhile, thinks about taking Logan out of day care because she's bored. Kim instead convinces Christine to go down to a temp agency and get a part-time job that she's qualified for -- passing out teeny-weeny samples at the supermarket. Jimmy loves Christine's new job -- especially the free lunch part -- but Christine hates it so much she quits, and tries her luck again at the temp. This time she gets an even worse job, and quits it too. Jimmy overworks Greg so much that he's ready to quit working out himself, until Jimmy confesses that he's only been ""helping"" Greg to avoid taking care

When Jimmy gets accepted as a contestant on Big Brother, the thought of him and Christine having enough money to get their own place makes Greg takes drastic measures to see to it that Jimmy wins.