Who'd have thought super-glam singer Rihanna had a nasty streak?
The R'n'B sensation, 19, admits she used to have full-on physical fights with her two brothers.
'We used to fight and when I say fight, I don't mean arguments, I mean physically fight,' she tells hip-hop magazine Complex.
'I hit the older one in his face with a glass bottle. My mom was pretty upset.'
Blimey, we've heard of sibling rivalry but that's taking things a bit too far!
We know never to get in your bad books, Rih.