Reseachers this week revealed the real reason Mary from "Little House" lost her eyesight. Based on medical research and family letters, it's most likely that Mary Ingalls suffered from viral miningoencephalitis, which attacks the brain and spine. It had been thought that she had scarlet fever, but that disease was not known to cause blindness.

Researchers are now attempting to determine what gave Pa Ingalls such fabulous, thick curly hair!