William O'Shea was the older brother of Richard, who worked as a hitman for Johnny Ruffo. Despite the fact that Richard's loyalties were stronger towards Johnny, William was definitely a Tucker Stone man, in fact, he was pretty much Tucker's right hand man.
Tucker used Willy to be his personal chauffeur and bodyguard, among other duties. For this, Willie was well paid, and was highly respected by the other members of Tucker's organization.
Willy made no mistake about letting people know his loyalties were only to the West side crime syndicate. His dream was to one day run the operation, and he was ready to take over if anything unfortunate were to happen to Tucker Stone.
As for his younger brother Rick, anything could happen in this line of work, and considering Rick's lousy shot, he could easily get killed in a shootout. It would be a simple situation to orchestrate.
Although William had no plans to do away with his younger brother, this was a dog eat dog world, and any brother of his who was loyal to his enemies, just might find themselves having an unfortunate accident one day. And that day could be coming sooner than Rick O'Shea might realize, if Willie had anything to say about things.