Mother and Son - Season 6 Episode 3
The Family Feud

Maggie and Lorna are about to return home from England, and Robert has moved in with Arthur since Liz kicked him out. Once Robert finally leaves, and the sisters return home, Arthur is not surprised to find the sisters are not speaking, but it is over something that Lorna said about Arthur. This prompts a family meeting with everyone, and they turn against poor Arthur, who discovers what his family really thinks of him.