The band's debut album Light Me Up was released on August 30, 2010 in the UK, where it debuted at number 6, as well as at number 18 in Ireland.The first single "Make Me Wanna Die" was released on May 30, 2010, while the second single "Miss Nothing" which was released on August 23, 2010 peaked at number 39.She is also known for portraying the character of Jenny Humphrey on the CW teen drama series Gossip Girl (2007–2012) and Cindy Lou Who in the film Dr. She studied dance at the Center of Creative Arts in St. Momsen was signed with Ford Models at a very young age: "My parents signed me up with Ford [Modeling] at the age of 2. I was working constantly and I didn’t have a real life." She began acting professionally at three years of age in a 1997 national commercial for Shake 'n Bake. Momsen is included on the list of Unclaimed Coogan accounts for performing children whose partial childhood earnings are mandated to be put in a special fund but who have yet to claim their earnings.No 2-year-old wants to be working, but I had no choice. Momsen attended the Professional Performing Arts School in Manhattan for high school alongside Connor Paolo, Gregori Lukas and Sarah Hyland.Two months after she covered French magazine Rock One's.Momsen appeared on the cover of FHM’s March 2012 edition and FHM ranked Momsen #29 in its 2012 Hot 100 issue.She also made her debut Maxim cover in the November 2013 issue.Momsen has said that "music is where I can be me", stating that "acting is easy.
She is known for being the lead singer and frontwoman of the American rock band The Pretty Reckless. Although, she says now that she is older she is not a religious person.
She also auditioned for the title role in Hannah Montana, and was in the top three, but the role was instead awarded to Miley Cyrus—a decision that Momsen was happy with in retrospect.
In 2007 she starred in the Walt Disney Pictures film Underdog, as Molly and as Jennifer in the movie Paranoid Park, directed by Gus Van Sant.
It was then announced that the actress would be scheduled for an indefinite hiatus from the show, which ultimately resulted in her leaving the series as a regular cast member, following the completion of the fourth season in 2011.
Later that year, on August 16, 2011, Momsen told Elle magazine that she had quit acting to focus on her music career.