Chicago Heights was originally a separate Mafia Family with its own Mafia bosses. Antonino Sanfilippo was the first. He was killed in 1924, followed by Phil Piazza. He was killed, I think, in 1926. Then the Capones took over under Dominic Roberto. Torrio had already established a foothold there earlier.

I recommend Matt Luzi's book The Boys from Chicago Heights for more info.