Where did the knife that killed Michael Carroll come from? Was it in his daughter Maddison Hickson's hands during the entirety of the fatal confrontation inside a home at Tenambit on January 16, 2021.
Or was it Mr Carroll, a man with a history of violence and a propensity to use weapons, who was initially armed with the blade before Ms Hickson disarmed him and, fearing for her life, twice stabbed him in the chest.
It is one of the crucial questions that a jury will have to answer as they look to determine whether Ms Hickson was defending herself when she stabbed her dad during a volatile argument at a house in Ronald Street.
The jury will retire to begin deliberating on Tuesday.