Solange Knowles was reportedly "provoked" by Rachel Roy before her attack on Jay-Z in a lift at the Met Ball 2014.
New claims have emerged that the singer had a heated confrontation with Roy for getting "too close" to the rapper and the situation escalated to the extent Beyonce warned the designer not to talk to her sister.
According to industry gossip website AllHipHop.com, Solange didn't like the fact Jay-Z was chatting to Roy - the ex-wife of his former business partner Damon Dash - and decided to voice her disapproval.
Despite Solange and Roy formerly being friends - and even posing together on last year's Met Ball red carpet together - this is the incident that reportedly sparked the attack on Jay-Z. The fact he allegedly told her off for causing a scene probably didn't help either.
However, relations between the two have apparently been awkward for some time due to Beyonce's husband's failed promises to make Solange a star.
A source told MailOnline: '"Jay keeps telling her to give him some time and he will sit down and write with her and then get her into the studio but he hasn't done it yet."
They added: "Solange's album is coming out soon but there is no buzz about it, which is a bad sign within the industry."
This is the latest rumour in the saga, following yesterday's reports Solange lashed out because she was annoyed about Jay-Z's plans to party with Rihanna after the ball.
Meanwhile, Beyonce has posted pictures of herself with both Solange and Rihanna on Instagram seemingly in a bid to show there is no bad blood between the three and the rumors are incorrect. We're pretty sure there'll be a new rumour tomorrow...
WATCH! The now infamous Solange attack on Jay-Z