An argument over Johnny Depp's dying mother led to the alleged bust-up between the actor and his estranged wife Amber Heard.
Johnny's two children - Lily-Rose, 17, and 14-year-old Jack - reportedly did not want Amber at Betty Sue Palmer's bedside during her last days, which prompted a heated row between the Hollywood icon and his wife that allegedly led to him hurling a phone at her.
A source told The Sun newspaper: "Jack and Lily-Rose have never seen eye-to-eye with Amber but put up with her for their dad's sake.
"But they were certain they didn't want her at Betty Sue's deathbed - and that caused huge friction.
"Johnny told Amber but says she acted 'like a petulant child'. That's when things turned nasty and a huge row erupted."
Meanwhile, it has also been claimed that Johnny - who has been handed a temporary restraining order - was "driven insane" by fears the 30-year-old was cheating on him with Cara Delevingne.
Johnny - who has denied the abuse allegations - is said to have been suspicious that his bisexual wife and the British model were "making a fool of him".
A source close to the situation previously said: "Amber's friendship with Cara, which grew closer and closer over time, brought about the beginning of the end for her marriage to Johnny.
"They used to party together a lot and made no attempt to hide the fact that they were quite flirty. Amber always made her bisexual tendencies quite obvious.
"But that would spark furious rows with Johnny, who hated how indiscreet she was being. On one occasion he even screamed at her, 'You're making a fool of me'."