Chastity Bono announces sex change

Political and social activist Chastity Bono – the only child of entertainers Cher and the late Sonny Bono – began undergoing a sex change shortly after her 40th birthday on March 4.

A spokesman for Bono, born a girl to Sonny and Cher, says he "has made the courageous decision to honor his true identity" and began the sex-change process earlier this year. Publicist Howard Bragman said Bono is proud of his decision and hopes "that his choice to transition will open the hearts and minds of the public regarding this issue."

"Cher is very supportive and has known about Chastity wanting to do this for a very long time," a source tells PEOPLE. "This will be a long process but it's something Chastity has wanted to do for many years."

The 40-year-old writer, activist and reality-TV star came out as gay 20 years ago, Bragman said.

In the book "Family Outing: A Guide to the Coming-Out Process for Gays, Lesbians, & Their Families," Bono describes the realization of being "somehow different — specifically different from who my mom expected me to be."

A message left with Cher's representatives was not immediately returned Thursday.

Bono's second book, "The End of Innocence: A Memoir," details how relationships with Joan, a lover, and Sonny and Cher changed after coming out.

In 1995, Bono posed for the cover of the gay magazine The Advocate and began working for the Gay and Lesbian Alliance Against Defamation (GLAAD).

Parents Accepted

In 1992 she began a serious relationship with "Joan," a woman 20 years her senior, which ended tragically when the woman lost a battle with lymphoma and died in 1994. Finally, in 1995, Bono publicly embraced gay activism by posing for the cover of the gay magazine The Advocate, proclaiming herself "out at last" and taking a high-profile job with the Gay and Lesbian Alliance Against Defamation (GLAAD).

Bono's activism transformed her relationship with both parents, sparking pride in her mother, who "got to see me as a full person for the first time," said her daughter. But Sonny was by then a Republican congressman whose conservative agenda did not include gay causes such as legalizing same-sex marriage. "He accepted me, but his politics didn't," Chastity recalled. (Sonny Bono died in January 1998.) "I didn't talk to him about it, but I was angry."

More Hot Stories:
david carradine death scene photo
Johnny Palermo dies in car accident