O'Reilly hockey players: who's related

The 4 O'Reilly players we cover who reached the NHL or have a O'Reilly relative in hockey, grouped into the families our sources record. Sharing a surname isn't a family tie: a player listed apart has no family connection on record with the others, which isn't proof that there is none.

Family ties come from Wikidata and Wikipedia; only relatives who play or played hockey are listed.