A Christmas Gift

S5, E7: It's coming up to Christmas, and Mike's mum is staying. Betty wants to be helpful, but it isn't long before she is driving Mike and Alison round the bend. Betty has overstayed her welcome, but Alison and Mike don't quite have the heart to tell her. Just as she decides to leave of her own volition, Betty suspects something is terribly wrong at Button House. She adopts extreme measures to make the house safe and in doing so endangers the resident Ghosts - will they come out of this unscathed?