Teamwork: Brother helps sister with Leigh's disease nail slam dunk

Give this brother an award for the best assist in basketball history.

Abby MacCurtain, 9, of Plymouth, Massachusetts, and her brother, Tomas, were playing basketball outside of their home on May 14 and recorded an epic slam dunk.

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In the video, recorded by their father, Greg, Tomas is seen holding the basketball hoop at an angle so Abby is able to dunk it into the net.

“You can do it,” Tomas is heard encouraging his sister in the video. And, with her brother’s assistance, Abby’s successful dunk garners applause from her proud brother.

Abby was diagnosed with Leigh’s disease, a rare inherited neurometabolic progressive disorder, at just 9 months old. Doctors told her parents that she might only have two years left to live, but she proved them wrong.

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She not only dunks basketballs, but she even occasionally joins her firefighter father in marathons and triathlons using specialized equipment designed by Danish company Triobike.

Storyful contributed to this story.