HBO Real Sports

Lucas And Noah Aldrich

Competing in triathlons is tough enough. For 11-year-old Noah Aldrich of Idaho, it is even more challenging. That's because Noah takes his disabled 9-year-old brother, Lucas, with him on the course.

Lucas has lissencephaly, a rare neurological disorder that limits his ability to walk and talk.

During the swimming portion of a triathlon, Lucas lies in a raft and Noah pulls it. In the biking and running sections, Lucas sits in a cart that Noah tows or pushes.

HBO's Real Sports takes a closer look at the special connection between these brothers in its latest episode that premieres Tuesday at 10 p.m. ET/PT. Here's a preview: