Four-year-old hits Wahlberg where it hurts

Mark Wahlberg's son loves to punch him "in the nuts".

The 'Broken City' actor - who has children Ella, nine, Michael, seven, Brendan, four, and Grace, three, with wife Rhea Durham - is proud of his "nice" family but admits they have mischievous streaks, though they always manage to make him laugh, even when he's in pain.