Tim Gunn on Working With Taylor Momsen: "She Was Pathetic"

Tim Gunn is raring to go to give Gossip Girl star Taylor Momsen her wake-up call! The Gossip Girl guest star says Taylor was "pathetic" and a "brat" on set.

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Tim has been on a roll speaking his mind lately and he's ready to give Taylor what he thinks is some much need advice!

After working with the actress/singer on the set of Gossip Girl for a guest spot in the new season, Tim got a taste of what Taylor is really like.

"What a diva!" he told E! News of what it was like working with Taylor. "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?' "

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While he didn't call her out on her behavior in person, Tim thinks her cast members should!

"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?' " Tim said. "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.' ''

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"I learned from teaching to stick with the topic, I don't get involved in character appraisals," Tim added. "I'd just ask her 'Do you want to share with me why you're always on your phone?' At one point the director leaned in and whispered to me, 'This is day in, day out, my life.' She annoyed the entire crew."

As for the rest of the cast? Tim said they were all a "delight" to work with!