They do that if you have a relative, or someone with the same last name, racing anywhere in NASCAR. Brad's brother, Brian, and his Dad, Bob are currently active in NASCAR. Sometimes you'll see just a first initial...that means the relative or namesake has a diiferent first name, ie M.ike Wallace and D.arrel Wallace...not related, but still have same last name, so they use their 1st initial.
Clear as mud???