There were 2 popular blues harmonica players that went by the name "Sonny Boy Williamson"

• Sonny Boy Williamson I, also known as John Lee Williamson was an American blues harmonica player, born in Jackson, Tennessee, whose first record 'Good Morning, School Girl' was a hit in 1937. He was widely popular throughout the whole southeast and practically synonymous with the Blues harmonica for the next decade, making his a commonly used stage name by the time he was murdered in 1948.

• Sonny Boy Williamson II, also known as Aleck "Rice" Miller, was the more famous of the two. He recorded for Chess Records in the 1950s and 1960s. He was born on December 5, 1899, in Glendora, Mississippi, and died on May 25, 1965 in Helena, Arkansas. Also see [1].

See also

• Wikipedia:Non-unique personal name