As a former football coach, Joe Gibbs knows what head injuries can do to the human brain. This week, it became personal when his son, J.D., began treatment for symptoms impacting brain function.
Gibbs owns the NASCAR racing team that carries his name. J.D. is team president. Sunday, the father spoke of the son, calling him "my hero."
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"J.D. through his entire life has probably been the most courageous person I've ever been around or known," Gibbs said Sunday in a media conference at Martinsville Speedway. NASCAR's Sprint Cup Series ran the sixth race of its 2015 at the track.
For now, Gibbs said, there are "very few answers" from doctors about J.D.'s condition. Doctors believe his symptoms that include speech and processing issues are a result of head injuries.
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Gibbs, 46, became the president of his father's race team in 1998 after brief stints as both a Truck Series driver and Xfinity Series driver.
"We've been dealing with this for about six months," Joe Gibbs said in his media conference. "Basically, what the doctors said is that they just really don't know. J.D. has lived a very active lifestyle in all the things he's done. Physically, he's loved all sporting events, everything from football to snowboarding and racing cars to racing motorbikes.
"We can't point to any one serious thing (injury) that happened to him, but certainly an injury possibly led him into some of the symptoms he's experiencing now."
Gibbs took no questions on Sunday.
J.D. Gibb's son is recovering from leukemia. Taylor Gibbs was diagnosed with the disease at age 2. "We fought through that for three or four years, and Taylor's doing great today," Gibbs said.
For now, Joe Gibbs is taking responsibilities normally handled by J.D., while the younger Gibbs has cut back on at-track activities.
The Gibbs family relies on faith, an anchor that is especially necessary now.
"J.D. got up at our team meeting earlier this week and basically said, 'I know that God has a plan. God puts us through things for a reason,' Joe Gibbs said. "I think J.D. gains his strength from the faith that he has a personal relationship with the Lord."
Contributing: USAToday.com, NASCAR.com