1. Troian Bellisario Ilya S. Savenok If it wasn't for Billboard Dad and Troian Bellasario's convincing role as a young girl that likes to hang out by the pool, her acting career might not have taken off and then Pretty Little Liars wouldn't even exist. Facts! 2. Eric McCormack Gregg Deguire / Getty Images Eric McCormack would literally never have gotten the part of Will on Will and Grace if he hadn't shown off his exquisite acting chops as Mary-Kate and Ashley's dad in Double, Double, Toil and Trouble. Look at him fake drive that car. It was impressive and I wasn't the only one who noticed. 3. Megan Fox Brendon Thorne She's Brianna Wallace and she gets what she wants and this winter break she is gonna become a huge star thanks to Mary-Kate and Ashley for casting her in Holiday In The Sun as the HBIC!!!! 4. Michael Cera Angela Weiss / AFP / Getty Images Michael Cera should be thanking his lucky stars that he got to have a 30-second scene in Switching Goals because his line "I have delicate bone structure" basically set him up to be George Michael Bluth. 5. Dr. Drew Allen Berezovsky / Getty Images If it wasn't for Mary-Kate and Ashley casting Dr. Drew as their dad in New York Minute then honestly we'd all be sitting here like...Dr. Drew WHO? That was the role of a lifetime. 6. Jason Clarke Francois Durand / Getty Images Jason Clarke wouldn't play the weirdo bad guy in every movie he was in if he didn't play the weirdo bad guy in Our Lips Are Sealed first. 7. Ethan Peck Nicholas Hunt / Getty Images Now he's in Star Trek but once upon a time he was just a kid in a bucket hat putting on a fake French accent. But I'm know for a fact that his extremely accurate French accent was responsible for agents noticing him and making him a star. 8. Theo Rossi Jamie Mccarthy / Getty Images Yeah that's right! He went from kid in a survivor buff to an actor on Sons Of Anarchy. MK&A took a chance on him and it paid off. 9. Willie Garson Alberto E. Rodriguez / Getty Images Before he was in Sex And The City he was a pizza-eating FBI agent in Our Lips Are Sealed and he KILLED that role, clearly opening doors for him everywhere. 10. Jesse Spencer Valerie Macon / Getty Images His Winning London role basically won him a first class ticket to famous-personville!!! Last I heard critics are still raving. 11. Austin Nichols Frazer Harrison / Getty Images Holiday In The Sun forced the world to recognize his talents and good looks and therefor it made him. 12. Sarah Paxton John Lamparski / WireImage Sarah Paxton once played a girl named Patty in Mary-Kate and Ashley's Christmas Collection. Her role as Patty cemented her future as Aquamarine in Aquamarine and that is the truth. 13. Cloris Leachman Jason Laveris / FilmMagic Her first 50 roles AND the Oscar she won in 1971 are basically nothing compared to the opportunity given to her to play a witchy aunt in Double Double Toil and Trouble. Mary-Kate and Ashley made her. Thank you Mary Kate and Ashley for your service to the celebrity community!