Bening`s daughter Kathlyn wants to undergo gender reassignment
The 18-year-old is said to currently be living under the name Stephen Ira and wants to have the surgery now she is an adult - despite her parents being upset about the issue.
A source told National Enquirer magazine: "Warren is beside himself over the situation with his daughter Kathlyn. He and Annette have tired to deal with this over the years when their daughter was younger, but she`s determined to go ahead with the transgender operation, just like Chastity Bono.
"She repeatedly told her parents that `once I turn 18?, she would take matters into her own hands."
Kathlyn is the oldest child for the Hollywood couple, who also have a son, Benjamin, 15, and daughters, Isabel, 13, and Ella, 10.
Chastity Bono - the daughter of singer Cher and her former husband Sonny Bono - recently underwent the final stages of gender realignments surgery completing the legal transition from a woman to a man, and is now known as Chaz.