Violinist Natalie pelted Simon Cowell and his fellow BGT judges with eggs during Saturday night's final, and has since said she was "taking a stand" against musicians "miming" on the show.
Now, Natalie's mother Patricia has spoken out and insists she didn't know that her daughter was planning to invade the stage.
Speaking to the Daily Star, she said: "We were as shocked as anyone when we saw her up on stage throwing the eggs.
"I was speechless. But it wasn't malicious."
Natalie stormed the stage during Richard and Adam's performance before being branded a "stupid cow" by Amanda Holden once she had been dragged away.
The musician has since apologised for the attack and said it was a "silly thing to do". But she still said Simon was "dreadful".
Meanwhile, Simon has not let the incident get to him and was pictured looking in good spirits at the BGT wrap party.
He has also tweeted his fans, joking: "I don't think eggs should be allowed on talent shows. Discuss?"
However, Richard and Adam have spoken out, saying Natalie had "destroyed their chance of winning". Following all the drama, shadow dancers Attraction won the show.
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