Susan Olsen/Facebook

As the latest star to speak out in favor of same-sex marriage, Susan Olsen, who played Cindy Brady on the iconic 1970s sitcom " The Brady Bunch," said that if her on-screen dad Robert Reed had been "allowed to form a relationship with another man, he would have been the best husband ever."

In a heartfelt open letter posted on her Facebook fan page last week during the Supreme Court's hearing on gay marriage, Olsen wrote, "As a child, I was BLESSED to have another father figure in my life. So I really can honestly say, 'My Dad was Gay.'

"I can also say that being gay killed him," she added.

Reed died in 1992 at age 59 from colon cancer, with HIV listed as a significant contributing factor to his death. Following his death, cast members, including Florence Henderson, who played his wife on the show, and Barry Williams, who played Greg Brady, acknowledged that he was a closeted homosexual.

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Olsen wrote in last Wednesday's post that because his homosexuality was "so taboo, he could never make peace with himself."

"He never allowed himself to have a genuine love. He was forever taunted by his own disdain for the natural inclinations that he was BORN WITH," she wrote.

Reed briefly married fellow Northwestern student Marilyn Rosenberger, and they had a daughter before divorcing.

"Bob was a family man," Olsen wrote. "Had he been allowed to form a relationship with another man, he would have been the best husband ever and might still be alive. But Bob could not be at peace with this because the people surrounding him shoved their own judgment down his throat and, sadly, he bought into it. He thought he was wrong."

In addition to her tribute to her "gay dad," Olsen posted a picture of herself from the iconic series praying beside Reed and Henderson, along with the caption, "Please God, let the Supreme Court know that you think it's OK for gay people to marry."

After receiving thousands of comments, many of them positive, Olsen wrote on her Facebook page Friday, "Many thanks to all the wonderful people (nearly as many straight people as gay!) who thanked me for expressing my love and respect for Robert Reed and compassion for the LGBT community. Your notes were incredibly touching and made me glad I said what I did."