Before her shocking attack on brother-in-law Jay Z on May 5, singer Solange argued with designer Rachel Roy.

According to sources, Solange, 27, allegedly had become drunk and belligerent while attending the Met Ball. 

From Page Six:

“Solange had too much to drink and was out of it by the time the performances started after the dinner at the Met Ball — she was dancing like a crazy person,” a source said.

Another source said the “Losing You” singer argued with Roy shortly after arriving at the Standard and Beyoncé, 32, came to her defense when another guest attempted to intervene.

When the female guest asked Solange, “‘What is your problem?’ Beyoncé defended her sister and told the guest, ‘You don’t get to speak to my sister that way.’”

Upon making their exit from the hotel’s venue, the Boom Boom Room, and entering an elevator, Solange “flipped out over something Jay had said, that she took the wrong way,” reports Us Weekly. “Not sure what it is was, but she greatly overreacted.”

Read more at Page Six

E! Online reported that Beyoncé  and Solange flew to Costa Rica shortly after the elevator scene. Reports say the two might have taken the trip for Kelly Rowland’s wedding.

Check back for updates.

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