Beyonc�'s Sister Attacks Jay-Z in Elevator (VIDEO)

With Jay-Z and Beyoncé being the superstar couple that they are, it's sometimes easy to forget that Solange Knowles exists. Solange is out to rectify that, it seems.

According to TMZ, there's footage of Beyoncé's sister attacking Jay-Z in an elevator at the Met Gala. In the security video, you can see Solange get up in her brother-in-law's face and exchange some heated words with him. Shortly after that, she starts hitting him and even kicking at him as others try to pull her away.

Perhaps the best thing about the video is how calm Beyoncé is, as she stands to the side. Either she doesn't think her sister can do much damage, or she's used to these kinds of outbursts from her.

Interestingly, one of the security guards hits the emergency stop button, and there's a good reason for it: Shortly after the fight died down, the three celebs had to step off the elevator into a crowd of photographers covering the event.

The reason for the fight is still a mystery, though. What could have gotten Solange so upset that Beyoncé wouldn't have also been upset about, especially consider the fact that it lead to blows?

Check out the video, courtesy of TMZ, below: