Hollywood actor Mark Ruffalo recalled his experiences as a parent for his role as The Hulk in new film The Avengers - because having children sometimes makes him angry.
Ruffalo claims his short temper helped him fine-tune his ability to act out the moment ordinary man Bruce Banner converts to the rage-fuelled superhero.
He tells the Ottawa Citizen, "I have a hair-trigger temper and I have lots of practice: A parent who doesn't yell at his kids isn't spending enough time with them."