We caught up with the Gossip Girl star and asked if she had anything to say in response to Gunn's claims she is a "sad and pathetic brat."
"I don't respond to that," she said with a smile at last night's launch of of Madonna and daughter Lourdes' new Material Girl fashion line at Macy's Herald Square in New York.
Then someone in Momsen's camp came to her defense, yelling, "We don't respond to name calling!"
Last week, Gunn had offered up some unsolicited advice for the 17-year-old actress, saying she paid more attention to her BlackBerry than to memorizing her lines on the set of her show, and that he'd like to give her a good talking to.
"What a diva!" he'd told E! News about Momsen. "She was pathetic, she couldn't remember her lines, and she didn't even have that many. I thought to myself, 'Why are we all being held hostage by this brat?' "
"I'd say, 'You know young lady, there are hundreds of thousands of girls who are just as attractive and even smarter than you. Why are you acting like this show is a huge burden on you?' She was on her phone during every break, I wanted to tell her, 'If you weren't on your BlackBerry, you can retain this stuff.' ''
Maybe Momsen was humbled by Madonna, whom Momsen called "an amazing person" who was an "honor" to work for.
"She's a mother, and a cool mother, and right now I'm focused on Madonna and my band. Lola and I collaborated on putting looks together and Madonna had some input later. It's such an honor. She's Madonna."
As for people bashing her?
"It's about owning it no matter what anyone says," Momsen said. "This is who I am and this is who I am going to be. It's about every girl being true to themselves."
Sounds like she's just trying to make it work.
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