Based on the context and the answer, generate a question. 

Context: Mum thought he was going to have another heart attack he was getting so wound up . But she managed to calm him down . I must admit I have N - E - V - E - R heard my dad swear like he did when he was telling me about it . So , fat club tonight , then cooking a curry , waiting for S to get home ( yup , he 's working again bless him - almost as bad as me ! )

Answer:

Anger involves a physical reaction that raises the heart rate and could possibly lead to a heart attack



Why did the anger of the speaker 's father make their mother think he might have another heart attack ?