Jacob Lemay, now 9, knew he was a boy before he could properly pronounce the word “transgender.”

“It's not how you act, or what you wear, or anything like that,” Jacob said of being trans. “It's just how you really are inside. ... You just feel like you just got put in the wrong body.”

With the support of his parents, Mimi and Joe Lemay, Jacob socially transitioned when he was just 5 years old. The couple said the journey was not initially easy, and they struggled as Jacob pulled away from them.

“It was almost like he was a thousand miles away from us and retreating,” Mimi Lemay said of Jacob’s pre-transition years. “It wasn't until we were able to say to him that we believed him, and that he could live as the boy he always knew he was — that's when we got our child back.”

The Lemay family initially shared their story with NBC News in 2015, when their son had just transitioned. Their story quickly went viral and remains one of the most viewed videos on the “NBC Nightly News” Facebook page. After their family’s journey was made public, the Lemays said they heard from other families all over the country.

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Now, Mimi Lemay has written a memoir titled “What We Will Become” about love, acceptance and change.

The Lemay family the summer Jacob turned 5. TDM Photography

When NBC News caught up with her to discuss the memoir and her family’s journey over the past several years, Mimi Lemay expressed how difficult things have been recently for the LGBTQ community, particularly transgender individuals. She cited the recent spate of bills targeting trans youth that have emerged across the country in the current legislative session. More than half a dozen states, most recently Ohio, have introduced bills seeking to ban gender-affirming health care for minors. This type of care, Mimi Lemay said, will save the lives of children like Jacob.

Jacob is now in fourth grade. He has a pet hedgehog named Trinket, and he loves hockey, jumping on his backyard trampoline and playing with his sisters. He is a typical 9-year-old boy in every way, except for being transgender. He said some of his friends know and some don’t. But to most kids, it’s just not that big a deal.

Jacob with his hedgehog, Trinket, and his pug, Luna Courtesy Mimi and Joe Lemay

Over the last five years, he has grown and matured, and he is more sophisticated now when he talks about what it means to him to be transgender. And since he has reached the early stages of puberty, Jacob has opted to take a puberty blocker. This is a completely reversible step endorsed by the medical community. It is also the very kind of treatment that some state lawmakers are looking to stop.

Joe Lemay said Jacob understands what his options are, and what each step in this process will bring.

“He's becoming educated on what future choices he'll need to make,” he said. “That's one of the reasons why he is, you know, taking a puberty blocker, so that we know he's had years to think this through.”

When asked what he wants the public to know about the transgender community, Jacob said, “I want people to know that it doesn't make you any different from anyone else.” He added that it’s not always easy to tell people that he’s transgender, but he thinks if people just understood it a bit more, the world might change.

“Most of the people aren't bad people,” he said earnestly. “They just don't really understand.”

Jacob Lemay with his mother Mimi. Courtesy Mimi and Joe Lemay

Mimi and Joe Lemay said their entire family now advocates for transgender rights. In fact, Jacob recently asked presidential hopeful Sen. Elizabeth Warren, D-Mass., a question at a televised town hall. The Lemays said they want to keep sharing their story to help other families with trans kids.

“Your child will be OK as long as you support them,” Mimi Lemay said. “There is no harm in saying to your child, ‘I see you … and believe you, and you are who you say you are.’”

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