Despite reports that the 17-year-old actress was placed on an indefinite hiatus from the CW hit Gossip Girl after acting increasingly erratic, a source tells PEOPLE she'll still be playing Jenny Humphry.
"She is still a series regular. She's still totally a part of the show," says the source. "Yes, you have seen less of her this season, but it's dictated by creative [executives]."
The source says as Blake Lively and Leighton Meester's characters went off to college, storylines – including the younger Momsen's Jenny – have just been harder to set up.
"They graduated high school ... [and] they found that it was hard to put all of them in the same environment in a natural way," says the source. "When you see Jenny they want her to be driving the story, not just hanging out with the mean girls back in high school."
And although Momsen has raised eyebrows with her behavior, including flashing the crowd during a concert with her band The Pretty Reckless last month, "this has nothing to do with her bad behavior or her music career," says the source. "She's still under contract and she's still a part of the show. She's just in fewer episodes."