Any ideas why Eloise from the 70's still looks so young? Older than the Eloise from the 50's. Clearly she ages when she leaves the island, and she ages on the island, but not as much.
Richard never ages, though.
Assume she's 18 in 1954. That would make her 41 in 1977. According to IMDb, the actress who played her in this ep is 37, so it's actually not that much of a stretch.