Life What is ALS, the rare disease making it ‘impossible’ for Roberta Flack to sing? November 15, 2022Natalie Neysa Alund, USA TODAYComments Off on What is ALS, the rare disease making it ‘impossible’ for Roberta Flack to sing? Roberta Flack manager announced Monday the singer has been diagnosed with ALS. Here's what you need to know about the rare, but deadly disease.