One secret Taylor Momsen is ready to tell?

Why—and how—she left her role as Jenny Humphrey on Gossip Girl ahead of The CW series' fifth season back in 2011. And when it comes down to it, after more than a decade of life as a child star, she wanted to return to her first passion—music.  

"[Acting] was a childhood thing that I got put into when I was 2 years old," Taylor told her onscreen brother Penn Badgley and his cohosts Nava Kavelin and Sophie Ansari on the Sept. 6 episode of SiriusXM's Podcrushed. "I wasn't making my own choices then. And literally, as soon as I got to an age where I could make my own decision—it was like a click. I woke up one morning and went, 'Wait a second. I don't have to do this. I can just plauy in my band, and tour, and write songs. I can just do that.'"

The 30-year-old—who has been the lead singer of The Pretty Reckless since 2009—continued, "I have the ability to create and live my life the way I want to live it. I don't know exactly what made that click, but it was like a light bulb went off. And I uprooted and kind of changed my life overnight."

But as the Underdog actress admitted, "Granted, a little more complicated to get out of a television show than that." So how did she navigate her exit from the show? As she noted, her negotiations—though she never specified exactly who with—required a few stipulations.

"They went, 'Well we can't let you out of your deal,'" she explained. "'But we can write you out of the show so you can go on tour. You can't act in anything else, though.'"

To which the How the Grinch Stole Christmas star added with a laugh, "I went, 'That's fine, that's not what I'm trying to do.'"

And despite having to find the workarounds, Taylor expressed gratitude for being able to pursue her music career.

"They're like, 'But if we don't write you in the episode, you're not in the episode,'" she added. "And they really allowed me to follow my dream, and so I'm forever grateful and thankful to them." 

As for Penn, he noted that the perception of Taylor as an actress isn't quite accurate.

"Essentially you've always been a musician, and you never really stopped," he reflected. "And that's always been drives you. And I think that this perception that anyone might have that you were an actress-turned-musician is really not the case."

And though Taylor may have left her days behind her, she's never forgotten her time on the Upper East Side. 

In fact, back in April, she reflected on her time as Little J when she shared a pic from the steps of New York City's Metropolitan Museum of Art—a now-iconic, then-go-to filming location for the series.

She cheekily captioned the April 2 post, "This picture feels familiar."

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