http://www.rollingstone.com/music/news/cleotha-staples-of-staple-singers-dead-at-78-20130222"I credit Pops' guitar and Cleedy’s voice with making our sound so different," Mavis Staples said, referring to her sister by a nickname. "Her high voice – Pops would take her to a minor key a lot. A lot of singers would try to sing like her."