Warren Beatty and Annette Bening's 18-year-old child is reportedly living as a man and planning to transition.
The student is said to be known as Stephen Ira and wears men's clothing to college.
The US tabloid magazine National Enquirer reports that acting pair Beatty, 73, and Bening, 52, are "devastated" by the news.
A source told the publication: "Warren Beatty is beside himself over the situation with his daughter Kathlyn.
"He and Annette have tried 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 [Chaz Bono].
