Recently Teen Mom 2 star Leah Messer-Calvert revealed to In Touch that her 4-year-old daughter, Aliannah, was diagnosed with a form of muscular dystrophy so rare that doctors told her Ali’s the only child in the world diagnosed with this particular disorder. 

Despite the family’s heartbreak over the shocking diagnosis, the reality star revealed to In Touch that it actually brought her closer to her husband, Jeremy Calvert, who became a stepdad when Ali and twin sister Aleeah were 2 years old.

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“Coming into this, he was like, ‘I love these kids,’” Leah says. “He was so willing to take them on but I don’t think he understood how serious Ali’s condition was when he came into our lives … I think it’s brought us closer and I think he looks up to me for having the strength that I’ve had.”

The mom of three added that the costs associated with giving Ali the necessary treatments have been a strain on the family.

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“Financially, it has definitely taken a toll,” she says. “One of Ali’s medical bills alone was $20,000, so it doesn’t matter how much money you make.”

Leah added that Jeremy’s work as a pipeline engineer brings in good money for their family, but the demanding schedule sometimes has him away from Leah, the twins and their youngest daughter — 11-month-old Adalynn — for days at a time.

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“He’s learning how to give work what they need and also give his family what they need,” she explains.

The challenge of raising a child with special needs has tested their marriage, and in one preview for Teen Mom 2, Jeremy is seen threatening divorce. But the young mom insists that they will never get a divorce — because they’re both too happy.

“We love each other unconditionally,” Leah gushes. “There’s no one else I could call my best friend, and that’s really the key to the family.”

Don’t miss Teen Mom 2 every Tuesday at 10 PM on MTV.

For more from Leah, be sure to pick up the new issue of In Touch Weekly, on newsstands now!

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