Berthe Erica Crow, the cleaning woman who worked for the other residents of Sunset Towers, and ran the Good Salvation Soup Kitchen with Otis Amber, is the former Mrs. Westing.  She had been divorced from Mr. Westing after the death of their daughter, and had become an alcoholic for a while.  She had been rehabilitated, and then chose to spend the rest of her life in humility and good works, though she could have been heir to at least a portion of Sam Westing's money.  She remains incognito for much of the book, and it is only revealed near the end that she has been in their midst all this time.

Crow is a difficult character to understand, because she is kept so deliberately shadowy during the large majority of the book.  Her devotion to Angela, who looks so very much like her own lost daughter, is tragic and hopeless, and one wonders what kind of monster Sam Westing might have been to drive this woman away so entirely.  Not all the questions about Crow's "hiding in plain sight" are answered, but by the end of the book it is clear that, among all the heirs, she has probably suffered the very most.  Her friendship with Otis Amber is touching.  That the wife of such a famous man as Sam Westing could have remained unnoticed for so many years seems unlikely, as do her common ways and willingness to work at such a hard job as being a cleaner, but her character is one of the most important in the book.  Much of the reason that the Westing Game was even conceived by Sam was to make some sort of reparations to her, and right some old wrongs.