It was never came easy for Leo when he began his early acting career as he had ever been rejected by an agent who perceived his name as sounded too foreign so that they suggested him to change his name into Lenny Williams. But he refused it and kept using his name. After that refusal, Leo went on to cast for the role of Garry Buckman in the 1990s TV comedy drama series, "Parenthood" where he met fellow actor Tobey Maguire and so both be best friends ever since.