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Abruptly departed: Alicia Goranson, second from left
Copyright © 2009, The Los Angeles Times
Played: Eldest daughter Becky
Lasted: Five seasons and 11 additional episodes in Season 8 (1988-1992; 1995-1996)
Why she left: Goranson left to attend Vassar College after five seasons. However, she returned during Season 8, sharing the role with her replacement, Sarah Chalke a.k.a. "Second Becky."
How it went down on air: Becky leaves home after five seasons to marry her boyfriend Mark and move to Minneapolis. After a temporary absence, Becky returns, this time played by Chalke.