Leah Messer has a difficult road ahead of her.

The mom-of-three breaks down in tears during tonight’s episode of Teen Mom 2, where she gives an update about her daughter Ali Simms, who was diagnosed with muscular dystrophy at birth.

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Leah takes her girls on a vacation and while out to lunch with her friend Maddy, she explains how much easier it is for Ali to get around now that she has a power wheelchair. Ali has struggled all her life with her diagnosis, which affects major organs in her body like her lungs, her heart, and she could even lose her ability to walk. Doctors warned Leah that Ali’s health could start to decline around her seventh birthday, which is quickly approaching.

“No matter what, I may never see the decline that they see. I guess I’ll handle that when it comes you know? It made it hard at 17, knowing something’s wrong with this baby that you love so f–king much,” Leah said as she wiped tears from her eyes.

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Watch the full sneak peek below and be sure to catching the next episode of Teen Mom 2, airing Mondays at 9 p.m. on MTV.

Scroll through the gallery below to see all of the Teen Mom stars with their kids!