Rob's numerous acting credits can't compare to what he considers one of his greatest roles: fatherhood. The Parks and Recreation star has an extremely close relationship with his two sons, Johnowen and Matthew.

Watch Rob talk about being a father Watch  

Rob writes candidly about his family and the experiences that made him the man he is today in his autobiography, Stories I Only Tell My Friends. Read an excerpt here. 

Exclusive: Go backstage with Rob Lowe Watch