Dimitrios Kambouris/Getty Images for Endometriosis Foundation of America Congratulations, Lena Dunham ! The day you've been waiting for has finally arrived. After becoming a most welcome poster child for waving goodbye to your 20s with open arms, the Girls star finally turns 30 today?and a very happy birthday to her! Of course, one might be forgiven for thinking that Dunham's been around a little longer. At just 24 years old, the outspoken celeb wrote, directed and starred in Tiny Furniture , which led to a little wildly popular HBO series called Girls .