Mother and son realize they are transgender at the same time

A Michigan father and his daughter realized they are transgender at the same time.

Eric Maison and his daughter, Corey, once formerly known as mother and son, told PEOPLE they had been watching a transgender documentary when they realized that their personal identities and genders also didn't correspond with their birth sex.

"That's when we both learned what it meant to be transgender, and realized that that explained both of us exactly," Maison, 39, told the magazine.

See photos of the father and daughter

Upon her revelation, the 15-year-old daughter came out shortly after watching the program, describing the transition process as "relieving."

"I was always sad and angry all the time, and I didn't know what to do about it," his daughter said. "I lost a lot of friends in the process, but the ones that actually did care stayed."

Eric Maison followed in his daughter's footsteps three years later when he came out as transgender. He says he prolonged coming out to support his daughter during her transition.

"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," the father added. "Honestly, I just thought it was me. I thought there was something wrong with my brain."

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After homeschooling his daughter for several years during her transition, Eric Maison says the school administration welcomed her when she rejoined school in Detroit. The school extended access to Corey Maison to use the girls restroom and locker room, an action for which her father praises former President Barack Obama's federal guidelines surrounding transgender rights in schools -- rights that have since been removed by President Trump.

Eric Maison disclosed his gender identity to his husband, Les Maison, in 2015.

"He took a minute to think and process that and he said, 'I love you, and no matter what we'll make this work,'" he said.

The couple has since said their family now feels "complete."