Roger Drummond was the son of William Drummond and Venetia Rutherford. Roger himself had eight children, including Captain Hugh "Bulldog" Drummond and John "Korak" Drummond-Clayton, who was adopted by Tarzan and Jane following his parents' deaths. The family - which descend from witnesses to the Wold Newton Meteorite strike - are described in Tarzan Alive by Philip José Farmer (which makes Tarzan's son Korak into an adopted son because there is insufficent room in the series of books for his baby son John to grow up enough to have the adventures portrayed in The Son of Tarzan).
In his article The Daring Drummonds, Brad Mengel has identified a further five offspring of Roger Drummond:
- Lorna, mother of Sydney Horler's Tiger Standish
- Roberta, mother of Donford Yates's Bill Chandos
- Alice, mother of Sydney Horler's Gerald Frost, aka Nighthawk (whom Mr. Mengel further asserts is the father of R.D. Wingfield's DI William Edward "Jack" Frost)
- Penelope, mother of John Creasey/GordonAshe's Patrick Dawlish
- William Drummond, aka the comic-strip pilot Ace Drummond (whom Mr. Mengel identifies as the father of Stephen Drummond from the television series Knight Errant)