Madhouse (1990)

Stockbroker Mark Bannister and his broadcaster wife Jessie have just moved into their own home and are nearly broke. When they get their mail, they discover that Mark's cousin Fred and his wife Bernice are coming to stay. Fred used to be wild, but now he's jobless and his domineering wife has decimated his self-esteem. Bernice is pregnant, and when she has an accident as she and Fred are leaving, she ends up stuck in bed for the last--six months of her pregnancy. Then Jessie's gold-digger sister Claudia and her son Jonathan arrive, and the next-door neighbors are forced to seek shelter at the Bannisters'. This brings Mark unwanted pressure as he tries to land an account with a multimillionaire, and stress almost costs Jessie her television job just as she's ready to hit the big time. Can Mark and Jessie EVER get their house back--without resorting to murder?