(MANDATORY CREDIT Ebet Roberts/Getty Images) COMO, MS-USA - MAY 07: Bonnie Raitt and Hubert Sumlin (L-R) at the unveiling of a Blues Trail marker honoring "Mississippi" Fred McDowell in Como, Mississippi on May 7, 2009 in United States. (Photo by Ebet Roberts/Redferns)
(MANDATORY CREDIT Ebet Roberts/Getty Images) COMO, MS-USA - MAY 07: Bonnie Raitt at the unveiling of a Blues Trail marker honoring "Mississippi" Fred McDowell in Como, Mississippi on May 7, 2009 in United States. (Photo by Ebet Roberts/Redferns)
(MANDATORY CREDIT Ebet Roberts/Getty Images) COMO, MS-USA - MAY 07: Bonnie Raitt at the unveiling of a Blues Trail marker honoring "Mississippi" Fred McDowell in Como, Mississippi on May 7, 2009 in United States. (Photo by Ebet Roberts/Redferns)
(MANDATORY CREDIT Ebet Roberts/Getty Images) COMO, MS-USA - MAY 07: Dick Waterman, former agent of "Mississippi" Fred McDowell and with Bonnie Raitt at the unveiling of a Blues Trail marker honoring "Mississippi" Fred McDowell in Como, Mississippi on May 7, 2009 in United States. (Photo by Ebet Roberts/Redferns)
(MANDATORY CREDIT Ebet Roberts/Getty Images) COMO, MS-USA - MAY 07: Bonnie Raitt and Hubert Sumlin (L-R) at the unveiling of a Blues Trail marker honoring "Mississippi" Fred McDowell in Como, Mississippi on May 7, 2009 in United States. (Photo by Ebet Roberts/Redferns)
