I encourage y'all to read this. Cedell had polio as a child, got trampled by stampeding customers in a bar when someone pulled out a gun, had a stroke late in life, but continued to perform despite his physical challenges. The polio stopped him from using his right hand to pick, so he learned how to use a knife as a slide with an "upside-down" guitar. Traveled and played with Robert Nighthawk.
https://www.nytimes.com/2017/10/01/obituaries/cedell-davis-bluesman-dies.html?hpw&rref=obituaries&action=click&pgtype=Homepage&module=well-region®ion=bottom-well&WT.nav=bottom-well
Here's an extended video someone made about him. There's a nice scene at 38-39 minutes with Cedell playing at a house party for a group of dancers:
https://www.youtube.com/watch?v=xmXgADPjuwg&feature=youtu.be&t=2316