EXCLUSIVE: Gossip Girl firebrand Taylor Momsen will continue to be a scarce presence on the CW soap during the second half of the season. Sources confirm that the increasingly volatile actress — who has appeared in a grand total of three episodes this fall despite being listed as a series regular — will begin an indefinite hiatus following next Monday’s episode. Although reps for The CW and producer Warner Bros. declined to comment, sources confirm that Momsen’s Jenny will be MIA for at least four episodes beginning with the show’s midseason finale on Dec. 6. The news comes as the 17-year-old Pretty Reckless singer’s off-screen antics continue to raise eyebrows.

Besides her barely-there wardrobe and expletive-laced tirades against peers such as Miley Cyrus, Momsen pissed off Project Runway‘s Tim Gunn who played mentor to ‘Jenny” in an episode that aired last month. Gunn blasted Momsen for her lack of professionalism on the set. “What a diva,” he told E! News. “She was pathetic, she couldn’t remember her lines, and she didn’t even have that many. I thought to myself, ‘Why are we being held hostage by this brat?’”

However, a Gossip insider maintains that the airtime for Momsen, an original cast member who has been on the show since the pilot, has been reduced for strictly creative reasons. Michael Ausiello will be contributing to Deadline.com and Movieline.com as he preps for the January launch of a new TV-centric website.

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