Miracle in Lane 2 (2000)

Myron Yoder's family was always proud of their eldest son Seth, a sports prodigy, but most of their attention goes to their younger son Justin, whose spina bifida condition means a wheelchair and constant, frantic care. During make-up chores for endangering grumpy neighbor Vic Sauder's sports car, he discovers a sport he finally hopes to excel in: soap-box cart racing, and gets highly experienced Vic to help and coach him. That proves promising and dangerous, but it also puts unbearable stress on the family cohesion as Seth now feels cruelly shoved aside.