A major milestone! Teen Mom 2 star Leah Messer got emotional while reflecting on her daughter Aliannah “Ali” Simms’s journey with a rare form of muscular dystrophy, and she shared a huge update in Ali’s diagnosis during part 2 of the Teen Mom 2 reunion special.

“I have so much good news about this,” Leah, 29, gushed to host Dr. Drew Pinsky in In Touch’s exclusive sneak peek of the Tuesday, August 3 episode. “I just partnered with a non-profit organization and sent her muscle biopsy from 2012 to OSU, Ohio State University …”

Leah trailed off and took a deep breath as she tried to choke back tears while talking about her 11-year-old daughter, whom she shares with ex-husband Corey Simms. “Guys, this has been one hell of a 12 years,” she said, starting to cry.

She said that OSU had done research on Ali’s biopsy to try to find “treatment” and “a cure” for titin muscular dystrophy, the rare form that Ali was diagnosed with when she was just 2 years old.

teen mom 2 leah reflects on ali muscular dystrophy

“Had I stopped looking for a diagnosis, I would never be to this point where 12 years into it, we’re finding a cure and research — and don’t tell me f—king science isn’t real,” Leah said, her voice shaking. “Cause that’s my daughter’s livelihood.”

Dr. Drew, 62, pointed out another big milestone in Ali’s journey, where her longtime physician, Dr. Tsao, revealed that there have been hundreds of other people in the world diagnosed with the same titin muscular dystrophy as Ali since 2012. With a larger number of patients to research, studies have found that patients can live into their 70s with the condition. It’s a huge update, considering that when Ali was diagnosed in 2014, the life expectancy for people with titin muscular dystrophy was only into their mid-20s.

“In spite of the treatment, her prognosis changed markedly,” the “Dr. Drew Podcast” host said. “I got so excited when I saw that, she could live a normal lifespan with this thing, it’s just she’ll have to deal with it, maybe. But that’s a huge deal.”

Later in the segment, Leah also shared updates on her battle with addiction and her breast cancer scare after she found a lump on her breast which, thankfully, turned out to be benign.

Part 2 of the Teen Mom 2 reunion special airs on MTV Tuesday, August 3 at 8 p.m. ET.

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