Trivia: Victoria Tennant hated the scene where her character was to be killed off so much that she refused to film it and walked off the set. The scene then had to be done by a stunt double.
Trivia: Flowers in the Attic author V.C. Andrews has a cameo appearance in the film as a window-washing maid.
Trivia: Victoria Tennant plays Jeb Stuart Adams' mother in the film, even though in real life she's only 11 years his senior.
Answer: When the children discover the cookies had been poisoned (revealed by the death of their pet mouse which ate part of one of the cookies), they suspect their grandmother. After all, she was the one who had been cruel to them all along. But eventually, they realise that it was in fact, their mother, Corinne, who was lacing the cookies with poison. She was doing so with the hope that the children would eventually die, seemingly from disease. In doing so, she would secure the family inheritance which was contingent upon her never having had children from her first marriage. They eventually confront their mother on the day of her second wedding, and a struggle ensues which ultimately leads to Corinne falling to her death from a balcony.
Michael Albert