Police warned about Hamzah Khan's safety
20 September 2013 Last updated at 14:25 BST
Amanda Hutton, 43, from Bradford, had denied the manslaughter of her son Hamzah Khan, whose body was found in a cot almost two years after he died.
Hamzah Kahn's father, Aftab Kahn, told the Bradford Crown Court that he had warned police about his former partner's behaviour and had said to them "All I want you to do is get a doctor to check Hamzah, check how undernourished he is, check how neglected he is, see how he is. "
Aftab Kahn has accused Amanda Hutton of being an alcoholic and claims that he tried to take Hamzah to a doctor but Ms. Hutton wouldn't let him.