"Teen Mom 2" Cast
"Teen Mom 2" airs Wednesdays at 10 p.m. EDT on MTV. MTV/Teen Mom 2

When Season 5A of “Teen Mom 2” wrapped in April, viewers saw Leah Messer-Calvert struggling with her marriage to Jeremy Calvert, and more importantly, her 4-year-old daughter Aliannah Simm’s health.

After revealing her daughter’s diagnosis of incurable muscular dystrophy in January, the reality-TV star is now sharing an update on her daughter’s condition ahead of the series Season 5B premiere.

“Ali is really smart and she’s well aware of her disease, but she doesn’t let it burden her,” Messer-Calvert, 22, told InTouch Weekly about her daughter. “She knows she’s different but she strives not to show it.”

While the “Teen Mom 2” star says her youngster is facing her diagnosis, which will most likely put her in a wheelchair one day, with strength, it isn’t without difficulty.

Ali Simms
"Teen Mom 2" star Aliannah "Ali" Simms in scene from Season 5A. MTV/Teen Mom 2

“The hardest thing is when Ali look sat me and says, ‘Mommy, my legs hurt,’” she admitted tearfully. “I know that there’s nothing I can do about it, and it’s so tough for me.”

Not only does Ali, who is the daughter of Messer-Calvert’s ex-husband, Corey Simms, 24, and sister of twin Aleeah, have to deal with the pain of her condition, the MTV series lead also says the public isn’t always kind.

“We’ve had people stare because Ali doesn’t walk like every other child her age,” she said.

Not matter what Ali’s future holds, Messer-Calvert said she and Simms, alongside Calvert, 25, and her youngest, Adalynn, 17 months, will always be there to pick her up when she’s down.

“We try to build up her self-esteem by telling that every time she gets up from a fall it means she’s stronger than before,” she said. “She’s going to be the happiest girl. I don’t care what I have to do to make it possible. I will never give up fighting for Ali.”

What can fans expect to see this season on “Teen Mom 2?” Other than Ali’s health issues, money also appears to be a big part of Messer-Calvert’s storyline this season. “With Ali’s medical bills, I’m drowning,” she admits in the program’s Season 5B trailer. “I’m freaking out!”

Catch the rest of Leah’s interview in the July 21 print issue of InTouch Weekly, on newsstands now.

“Teen Mom 2” returns on a new night, Wednesday, July 16, at 10 p.m. EDT on MTV.