Transamerica (2006)

Bree is on the verge of qualifying for her sex change surgery when she learns that her only heterosexual encounter many years ago yielded a son (Toby), a 17-year-old hustler who is in prison and is in dire need of a father figure. On advice from her therapist, Bree decides to meet him. Sullen Toby believes Bree to be a Christian missionary and has no clue that she's a he, or that he's her/his son. On these terms they head from New York to LA by car, Bree to have her operation and Toby to pursue stardom. What transpires between them is often hilarious, totally moving and surprisingly tender.

Official website: http://www.transamerica-movie.com/