This song was written by Victoria Williams, a 1980s / '90s folk singer who in 1994 developed Multiple Sclerosis. Pearl Jam gave the song wider exposure when they covered it on the "Sweet Relief" album, a collection Victoria Williams covers by several '90s Alternative bands … which benefitted Williams. I remember that the liner notes explained about her MS, and the fact that she lacked health insurance.
"She lived on a curve in the road, in an old tar-paper shack. On the south side of the town, on the wrong side of the tracks. Sometimes on the way into town we'd say: "Mama, can we stop and give her a ride?" Sometimes we did but her hands flew from her side. Wild eyed, crazy Mary."