Yes and no. In the comics and all animated versions, he has no biological siblings. In the Batman Forever Movie he had a brother added, Mitchell Grayson.
He was however adopted by Bruce, as was Tim Drake, so along with Damian Wayne and possibly Terry McGinnis, Richard Grayson may have 3 brothers as Bruce's son.
posted over a year ago
Side note, in an episode of Teen Titans GO, Beast Boy did depict a diagram with a SD Bald pacifier sucking baby listed as Dick's long lost brother... which is as close as anything besides Batman Forever comes to acknowledging a 4th Flying Grayson
