There seems to be an unwritten rule that if two characters have the same last name they will eventually turn out to be related.
Even when the spelling isn't the same, the characters end up being related in the unfolding of time as with Speed Saunders and Shiera Sanders--it took fiftty years for this to come to light. What about Greg Saunders (Vigilante)?
Roy Harper (Speedy/Arsenal) and Jim Harper (the Guardian) ended up closely related.
This is probably why Harvey Kent's name was changed to Harvey Dent, so no one would think he was related to Clark Kent. Dent might have been inspired by Lester Dent (pulp novel writer, famous for Doc Savage). Later the villain Dr. No-Face was in reality Paul Dent--must have been related to Harvey.
Brian Kent was the Silent Knight in the 6th century (THE BRAVE AND THE BOLD). He must have been an ancestor of Jonathan Kent.
Bruce Gordon became Eclipso. He had to be related to Commisioner James W. Gordon, surely. In fact, with Bruce as his first name, it's like the creators did a mash-up of Bruce Wayne and Jim Gordon.
Fan fictions have established a relationship between Margot Lane and Lois Lane (that Margot Kidder played Lois Lane is an odd twist of fate). Comic book posters seem to think Ralph Dibny is related to Walt Disney.
Wally West related to James West? Kid Flash does sound like the handle of a gunslinger.
Rick Starr (Star Ranger) may have been related to Bronco Bill Starr (Biron the Centaur/Comet the Super-Horse). And both to Ringo Starr.
James Robinson eventually would put anyone named Savage on the same family tree--Matt Savage (Trail Boss) and Steve Savage (Balloon Buster). Matt's son, Brian Savage, became Scalphunter (Ke-Woh-No-Tay) and was the father of Steve Savage. No connection to Vandal Savage?
Dick Grayson and Charles Grayson may have had family ties--Charles Grayson was the lab assistant of Robert Crane/Paul Dennis. Anyone named Kane or Cain has to eventually be in the Batman Family.
Larry Jordan was Air Wave in the 1940s--and his costume was green--so, of course, he had to be related to Hal Jordan (not to mention brothers Jim Jordan and Jack Jordan)--and Larry's son, also named Hal Jordan, was Air Wave II.