I've heard of them..My grandfather was the oldest of 13 children. His father had a job on the railroad in the late 19th early 20th Centuries. My grandfather was born in New Orleans and had brothers and sisters born in New York, Chicago, Pueblo Colorado, and even back in Sicily as they all had moved back there for several years before returning to America and settling on Taylor Street here in Chicago. My grandfather's youngest sister married a guy allegedly from that Denver Outfit and they settled in Pueblo. From what my Uncle would tell me, back in those days Denver answered to KC and KC answered to Chicago though it makes sense that they would have reached out to Spilotro in Vegas too.