User blog comment:RocksisDragonOP/Rocks D. Xebec IS MONKEY D. DRAGON/@comment-110.141.30.165-20200424091610

I think it's more likely that Rocks is Luffy maternal grandfather, Dragon fell in love with Rocks's daughter, had Luffy and then she and Rocks were killed and Dragon swears revenge on the Goverment.

We're gonna get Dragon's backstory eventually, Garp probably tried to make him a marine like tried to Luffy and Ace and failed. But unlike with Ace and Luffy his reasons for defying Garp are probably more dire.

Tbh I hope Rocks is really someone we've never seen before and isn't related to anyone we know.