Joseph's parents were Joseph (Giuseppe), Sr., and Rosalie (Rosalia), and his siblings were Carmela, Maria and Dominick (Domenico). They originally came from Sferracavallo and were closely connected to the LoCiceros and the Vassallos. Joseph grew up at 426 East 13th Street, very close to Saverio Virzi, a caporegime under Ignazio Lupo and later Toto D'Aquila. All of these families, and that of Frank Scalise, were related back in Sicily and a number of these relatives (fathers, uncles, grandfathers, etc) were identified as Mafiosi in Palermo in the 1890s, some even farther back. Also, Giovanni Riccobono, Joseph's uncle or great-uncle (I'll have to double-check on that), was one of the oldest men to enter Sing Sing Prison; he was convicted of murdering a police officer. In the early 1900s, under Virzi, the Riccobonos were known as notorious Black Handers. BTW, this isn't too far from where Lucky Luciano grew up; Luciano was close to several young men who grew up here and later became Gambinos, such as Frank Scalise, Joe Biondo, Steve Armone and others, but Luciano ended up going with Masseria.

He's definitely is a Riccobono and in the suicide letter it even confirms it (although it could be another johnny I doubt it) and I believe in the book the author was able to verify him being one or having a name change. The guy is so rich and the story is so extensive I don't think he'd make up baseline facts like those up. Apparently his father was a complete and utter psychopath who told him "if you are going to do evil, make sure you do it as evil as you can." or something like that.