Johnny Knoxville's nine-year-old daughter became addicted to gambling on horses after the JACKASS star took her to a racetrack for a day out.

Knoxville, 34, was shocked when MADISON showed a natural talent for picking winners - but he has learned to trust her advice.

He says, "Me and the boys like to go to the horse track and she likes to come with us. She's the only one who can pick 'em.

"One time she was at school and found out we were at the track. Every 29 minutes she would call with bets. She won seven races in a row."