The BUTTERFLY EFFECT (2004, US)
7-year-olds Evan (Logan Lerman), Kayleigh (Sarah Widdows), Tommy (Cameron Bright) and Lenny (Jake Kaese) suffer traumatic childhoods, especially Evan, who has periodic blackouts. When Evan grows up, he realises the blackouts are times when he has gone back in time to change the past, but every time he makes things worse.

This is a horrible movie with an anti them that stars horrible actor and anti Ashton Kutcher, so I would skip this one if I were you. ;)