The Real-Life Story of Mary Ingalls - Truth vs. Hollywood (Melissa Sue Anderson) 

Thank you finally somebody else realizes this

Yes and the Ingalls girls, minus Grace, who hadn't been born yet, had the measles for Christmas in 1876, while living in Burr Oak, Iowa.

Mary was blind from the time she was a young child

@@alexiswaller3065 She went blind at 14. And in the book, (and recent well researched bios) it is described quite differently. People didn't go to eye doctors much for check-ups, and "annual checks" were not a thing. She had a kind of stroke following a serious illness which may have been meningitis although that is disputed since the symptoms were not the usual ones for that disease. She had not been well for a few months leading up to that. Her eyes failed pretty quickly in the book--she gradually lost her sight after the stroke/disease, and was blind within a few weeks.