Wigger is the title of a wonderful 1974 children's book written by William Goldman, who also penned The Princess Bride and The Silent Gondoliers. It was illustrated by Errol Le Cain. The book's target age range is kids 7 to 10 years old. It's rather amazing that Disney or some other film company hasn't made a movie of this, though of course if anyone filmed it today, they'd have to change the now-unfortunate title.
In the book, Wigger is a little girl's beloved security blanket. Wigger was given to her by her parents, who died in a car crash. The little girl keeps getting sick, and her aunt and uncle take her to doctors, who can't figure out what's wrong with her. One night, she falls very ill, and they take her to the hospital. The doctors there realize what's wrong with her: she's drowning.
The little girl is literally drowning in tears; she hasn't cried at all since her parents died.
And then she loses Wigger, her last comfort.
As she lies close to death in the hospital, a Vietnam veteran learns of the little girl's plight, and sets out to find Wigger. He does, and when he brings the blanket back to the little girl, she is finally able to cry for her parents, thus saving her life.
Hmm, the above synopsis makes the book sound overly grim. It's not; it's a very sweet little book. It seems to be out of print, so if you come upon a copy in a used bookshop, you might want to take a second look at it.