Tarzan Twins — Edgar Rice Burroughs

When they were fourteen years old, Dick and Doc were attending an excellent English school where there were a great many future dukes and earls and arch-bishops and lord mayors, who, when they saw how much Dick and Doc resembled one another, called them "The Twins." Later, when they learned that Dick's father was distantly related to Lord Greystoke, who is famous all over the world as Tarzan of the Apes, the boys commenced to call Dick and Doc "The Tarzan Twins."