All grown-up: Child star transformations

Justin Bieber is only 19, and, according to his mentor Usher, is still in the midst of growing up. But between the tattoos, the ab workouts and those reckless driving accusations, Biebs is not the same "Baby" singer we met in 2009.Seven years ago, Jaden Smith was a baby-faced child star appearing with his dad Will in 2006's "The Pursuit of Happyness." Although he's once again starring with his father in this summer's "After Earth," Jaden isn't a kid anymore. The 14-year-old budding actor/rapper is one of many child stars who've transformed seemingly overnight into young -- and not-so-young -- adults. Along with her older brother Jaden, 12-year-old Willow Smith has blossomed since she first appeared alongside dad Will in his 2007 film, "I Am Legend." The actress and singer showed a more mature look this spring at the May 2013 premiere of "After Earth."Selena Gomez's appearance hasn't dramatically changed since she starred on Disney Channel's "The Wizards of Waverly Place" in 2007, but her work sure has. Now 20, Gomez has stretched herself with more mature content, like this spring's risque "Spring Breakers," and her suggestive new single, "Come and Get It."Macaulay Culkin turned a scream and an exaggerated expression into a blockbuster movie franchise when he starred in 1990's "Home Alone" at the age of 10. He went on to co-star with in 1991's "My Girl," but has in later years not been a huge fan of being on camera. In April, he ripped into paparazzi in the UK for trying to take his photo.Daniel Radcliffe's development has been watched by millions as he came of age in the "Harry Potter" movie franchise, which launched when he was 12. By 2007, Radcliffe was ready to show how grown-up he'd become and starred in "Equus" in London -- a stage production that required some nudity. Lindsay Lohan showed acting prowess at 12 when she played a set of identical twins in the 1998 remake of "The Parent Trap." Lohan went on to star in movies like "Freaky Friday" (2003) and "Mean Girls" (2004), but her tumultuous private life soon interfered with her career.