Beyonce and Jay Z
Solange Knowles has "definitely" lashed out at Jay Z before.
The 27-year-old singer was caught on camera in an elevator at the Met Gala afterparty at New York's Standard Hotel last week attacking her brother-in-law while his wife, her sister Beyonce, looked on and insiders say the couple appeared unfazed by the "tantrum" because it is common for her temper to explode.
Beyonce and Jay Z were reportedly unfazed by Solange Knowles' now-infamous tantrum in a lift because they are "used to" her explosive ways.
A source told Us Weekly magazine: "Solange has flipped her lid like that before.
"She is genuinely a sweet and nice person but she also keeps s**t real. She can take a small thing and it triggers her.
"This is not the first time this has happened. That's why Bey and Jay were so calm. They are used to this from Solange. It has definitely happened before."
At the end of the evening, Solange and Beyonce left in one car, while Jay Z - whose real name is Shawn Carter - left in another, and insiders say it was typical of the 'Crazy in Love' singer's "calm" nature to try and keep the peace.
A source said: "It is a testament to Beyonce's calm nature how she kept back and played the peacekeeper here. She is so calm and always the peacekeeper."
However, an onlooker at the Met Gala claimed the singer - who has two-year-old daughter Blue Ivy with her rapper spouse - didn't seem like herself throughout the evening.
The source said: "She wasn't smiling, was hardly with Jay, she was off with Solange the whole time."