Alien + 40 by Egantx7

Question 10

Within 2 years, how many years was Ripley cryogenically asleep between the events of Alien and Aliens? In the special edition of the film, we learn that her daughter, Amanda "Amy", had died two years before Ripley is found, and that Ripley had promised to be home for her 11th birthday.

57 years (55-59)