Stronger Than Life (1960)

An employee marries a wealthy widow with a daughter. Life continues between them and they have a little naughty child. The husband is jealous of the wife's interest in the daughter and doubts her behavior from the insitation of one of her relatives at home. He plans a plan to kill his wife's daughter by putting poison in a cocoa drink, but his son eats him by chance and dies. Suspicions are directed towards the mother and she is arrested for killing her son, and one of her relatives defends her.