Former NBA star Dwyane Wade now says that his son, Zion, knew he was transgender at the age of three.

Wade and his wife, actress Gabrielle Union, announced this month that they fully supported Zion’s quest to become a transgender girl named Zaya.

“Me and my wife, my wife Gabrielle Union…we are proud parents of a child in the LGBTQ+ community, and we’re proud allies as well,” Wade told DeGeneres during her February 11 broadcast. “We take our roles and responsibility as parents very seriously.”

But Wade is now adding to that support, telling Robin Roberts on Good Morning America that Zion has doubted his birth gender for years.

“She’s known it for nine years,” Wade said on Tuesday, according to BET. “She’s known since she was three years old. Along this way, we’ve asked questions, and we’ve learned. But she’s known.”

Wade added that he also had a feeling about Zion’s feelings, and it brought his own beliefs into question.

“I knew early on that I had to check myself,” he said. “That’s what I knew. I knew early on that I had to ask myself questions. I’ve been a person in a locker room that has been a part of the conversation that has said the wrong phrases and the wrong words myself.

“As I got older and I watched my daughter grow,” Wade said of Zion. “I had to go and look at myself in the mirror and say, ‘Who are you? What are you going to do if your child comes home and says, ‘Dad, I’m not a boy… I’m a trans girl.’ What are you going to do?’ That was my moment of real.”

Indeed, Wade claimed that it was his 12-year-old child who led the family to agree with and accept the idea of being transgender.

“She is the one who sat down with us as a family and said, ‘Hey, I don’t think I’m gay.’ And she went down the list,” Wade says Zion told them. “‘This is how I identify myself, this is my gender identity, I identify myself as a young lady. I think I’m a straight trans because I like boys.’ So, it was a process for us to sit down with our daughter and find out who she is and what she likes, and not put something on her.”

During his appearance on Ellen, Wade noted that after Zion told the family about his feelings, they began a quest for information.

“Now it’s our job to one, go out and get information, to reach out to every relationship that we have,” Wade told DeGeneres. “We’re just trying to figure out as much information as we can to make sure that we give our child the best opportunity to be her best self.”

Wade’s wife, also took to Twitter to celebrate Zion’s decision:

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