'Teen Mom 2': Leah Messer reveals daughter Aliannah has muscular dystrophy

leah-messer-aliannah-twitter.jpgEver since daughter Aliannah was born four years ago, "Teen Mom 2" star Leah Messer has been determined to find out why her daughter wasn't developing at the same rate as her twin sister, Aleeah. During the Season 5 premiere of the MTV show on Tuesday (Jan. 21), the reality star got the life-altering diagnosis.

It was revealed that Aliannah is suffering from a rare form of muscular dystrophy. The little girl's condition is degenerative and will continue to progress as she gets older, until it sadly confines her to a wheelchair.

"Eventually, Ali could be in the chair all the time," Messer tells Us Weekly. "But I've never seen her so happy. She chases Aleeah and doesn't fall down anymore."

Aliannah and Aleeah are Messer's children with ex-husband Corey Simms. The reality star has since wed Jeremy Calvert, changing her name to Leah Calvert. In February 2013, she welcomed her third child, Adalynn Faith.

"Teen Mom 2" airs Tuesdays at 10 p.m. ET on MTV.
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