According to ShowBlitz:
Kristen Stewart won't appear in "K-11," her mom's directorial debut, but big brother Cameron Stewart will, Variety's Josh L. Dickeyexclusively reports.
It'll be the first film credit for K-Stew's older sibling, but not for his co-stars Goran Visnjic, D.B. Sweeney andPortia Doubleday. The film stars Visnjic as a successful young record producer who wakes up after a three-day binge in a special unit of L.A. County’s Men’s Central Jail that's dedicated to vulnerable prisoners, a place ruled by a viper transsexual. (Cameron Stewart will play an inmate named "Sledgehammer.")
Though there was mass speculation that his kid sister of “Twilight” fame would also play a transgendered character, she is not involved in the project, alas. Shooting started July 18 at locations in Woodland Hills and Hollywood, and has moved on to the now-closed Sybil Brand correctional facility for women in Los Angeles County.