Eric Maison and his daughter, Corey, transitioned from their birth gender after realizing together that they are transgender

Mother and Son Transition to Father and Daughter After Realizing They Are Transgender

Eric Maison and his daughter, Corey, realized at the same time that they are transgender. The father and daughter — who were formerly mother and son — were watching a documentary about a transgender girl when they had their light bulb moment.

“That’s when we both learned what it meant to be transgender, and realized that that explained both of us exactly,” Eric, 39, tells PEOPLE.

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For years, both of them were uncomfortable in their bodies, but they didn’t know how to describe the feeling.

“I was always sad and angry all the time, and I didn’t know what to do about it,” Corey, 15, says.

“I knew that something was off, but I didn’t know what that was. I knew that I hated my body, I was very ashamed of it, but I didn’t know, cognitively, why,” Eric adds. “Honestly, I just thought it was me. I thought there was something wrong with my brain.”

Image zoom Eric Maison, before transitioning Courtesy Eric Maison

Image zoom Corey Maison, as a child Courtesy Eric Maison

Corey came out to her parents right after watching the film in 2012, a moment she said was “very relieving.” But Eric held on to her thoughts for another three years, for the sake of her daughter.

“I wanted to make sure that my child was taken care of. I wanted to do everything to make sure her transition was smooth and everything was in place,” he says. “As a parent, you want to put your kids first.”

Corey had issues at first — with her short hair, she became a target for bullies who would laugh and stare at her — but the teen discovered her true friends.

“I lost a lot of friends in the process, but the ones that actually did care stayed,” Corey says.

Image zoom Corey Maison, after transitioning Courtesy Eric Maison

And when she rejoined a local school in Detroit after taking classes at home for a few years, the administration was immediately welcoming, telling her to use the girl’s bathroom and locker room, and briefing staff members.

“There was an issue with a few parents complaining that there was a trans girl in the bathroom with their children, and the principal basically said, sorry but, President Obama set these guidelines and we’re going to stick by them,” Eric says.

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In 2015, Corey started hormone treatments, the final step in her transition, and Eric finally began to come out as transgender, first to his therapist, and then to his husband, Les.

“It actually came about by accident. [Les and I] were watching the movie The Danish Girl, and the transgender girl named Lili dies at the end, and when she dies I was crying so hard, more than you cry from a movie, and my husband hugs me and says, ‘Are you okay?’ And I said, ‘I’m sorry you’re stuck with a freaking Lili.’ And he took a minute to think and process that and he said, ‘I love you, and no matter what we’ll make this work,’ ” Eric recalls.

Image zoom Courtesy Eric Maison

He started taking testosterone, and then one year later underwent top surgery to remove his breasts.

“It’s kind of ironic that something needed to be removed from my body to feel more complete,” Eric says. “It was a major turning point for me. My biggest area of dysmorphia, my whole life, from puberty, from the time I started developing breasts, was my chest.”

Image zoom Eric Maison Courtesy Eric Maison

Now both Corey and Eric — who were featured in National Geographic‘s Gender Revolution issue — say they feel “complete,” and coming out as their true selves has made their lives better in every aspect.