As news of Solange Knowles' attack on her brother-in-law Jay Z spread on Monday night, the same question was asked - what prompted Solange's actions in the lift of the Standard Hotel?
Recent reports suggest it had something to do with Jay Z's plans to party after the Met Gala with Rihanna. Yep, now RiRi has been dragged into it.
The New York Daily News reports the dispute was caused by "the rapper's wish to keep the party going at a shindig hosted by RiRi," and Solange really wasn't happy about this.
According to a source, Solange was heard saying, "Why can't you go home?" before turning to her sister to say, "Why does your husband need to go to the club right now?"
Allegedly, Jay Z's response was, "You're one to talk," which sparked the start of Solange's violent outburst.
The report also suggests tension was caused earlier in the night when a few of Solange's friends tried to get into the Met Gala after-party by using Jay Z's name.
"They wouldn't leave and kept name-dropping Jay Z. They were pretending they were guests of his and not hers. Management went to Julius (Beyonce's bodyguard) and said there's a problem."
From wanting to go home, to trying to sneak friends into a party, the reasons behind Solange's behaviour continue to unfold.
As the latest story suggests Jay Z took his sister-in-law jewellery shopping in New York on Monday, it sounds like the two are making up. Phew.
Missed all the latest on the fued? Catch up with the video below:
And here's a reminder of Solange, Beyonce and Jay Z at this year's Met Gala, before the infamous lift incident: