SOUTH BEND, Ind.-- Twelve-year-old Natalie Holmes doesn't need her chair every day. It just depends on how much energy she has, and some days are better than others.

“My body steals energy from my stomach and my gut shuts down and I throw up and have to go to the hospital,” said Holmes.

Her disease, mitochondrial myophathy, is an energy defect that weakens her muscles. She needs all the energy she can get, so she cleverly disguises a feeding tube in her purse, but still gets tired a lot faster than her friends.

"Some days I’m tired when I wake up and I can tell that I’m going to be tired probably the rest of the day."   

It doesn't stop this seventh grader from serving as Northern Indiana's Goodwill Ambassador.

It's a special honor for a special girl. She applied and was hand-picked by the Muscular Dystrophy Association to help out at events. The association hosts events to raise awareness about muscle diseases like Natalie’s. And her job: give speeches to teach others about her condition

"I kind of dread it at first, but then I’m really okay with it once I get started"

When we asked her if she gets nervous she nodded yes. So to calm her nerves, or just calm her sweet tooth, she eats chocolate.

Her four-legged companion Micky stays by her side. He originally trained to detect her heart beat and breathing, but as she's gotten older, he's helpful in other ways.

"He helps me up and down the stairs because I'm not super stable on a lot of stairs."

Her disease may not yet have a cure but she doesn't let it ruin her positive attitude. She's just a normal pre-teen, anxiously awaiting the day her mom will let her sign onto Facebook.

“You said that when I turn 13 I can change my name on Facebook,” said Holmes.

Her mother’s answer: “We’ll see about it”