Marley family
From Monkey Island wiki
The Marley Family backstory is occasionally referred to in the games. In The Secret of Monkey Island Elaine tells Guybrush that her father made her promise to never fall in love with a pirate, but this would appear to be a white lie designed to get would-be suitors off her back. In Monkey Island 2: LeChuck's Revenge her grandfather is Captain Marley, who led an expedition to retrieve the treasure of Big Whoop, then later mysteriously disappeared during the America's Cup race. In Escape from Monkey Island Captain Marley is revealed to be none other than Herman Toothrot, a character who previously appeared in the first two games (although this contradicts some of the information in those games).
Elaine's mother and grandmother are not referred to in-game, and neither is there a mention of any sisters or brothers. It would seem most likely that she is an only child. Elaine's letter from her grandfather in Escape suggests that her parents did not get along with her grandfather.
Family tree
Horatio Torquemeda Marley----+----Unknown female | | Elaine's Father----+----Elaine's Mother | Elaine Marley----+----Guybrush Threepwood
