He was one of the most important figures in their early days, and yet he's often overlooked in most discussions about the Rolling Stones. Known as the "Sixth Stone," Ian Stewart served double duty for the World's Greatest Rock 'n' Roll Band as both their piano player and their road manager.

Born on July 18, 1938, "Stu," like so many other British kids, fell in love with American jazz and blues and took up both piano and banjo. In May 1962, he answered an ad placed by Brian Jones looking for musicians, and was soon joined by the other future members of the Stones. But when Andrew Loog Oldham began managing the band, he fired Stu because his looks didn't fit the rebellious image he was chasing for the Stones. Instead, he asked Stewart, who was a few years older and more disciplined than the others, to be the road manager.

"I'm still working for him," Keith Richards wrote In his autobiography, 'Life.' "To me the Rolling Stones is his band. Without his knowledge and organization, without the leap he made from where he was coming from, to take a chance on playing with a bunch of kids, we'd be nowhere."

Even though he was no longer a performing member of the band he affectionately referred to as his "little three-chord wonders," Stu still wound up on every Stones album made in his lifetime, with the exception of 'Beggars Banquet' and 'Their Satanic Majesties Request.' His playing can be heard on such tracks as 'Time Is on My Side,' 'Honky Tonk Women,' 'Brown Sugar' and 'It's Only Rock 'N Roll,' and he frequently joined the group onstage from 1969 to 1982. He also played on Led Zeppelin's 'Rock and Roll' and 'Boogie With Stu,' which was named in his honor.

Despite eschewing many aspects of the rock 'n' roll lifestyle, Stewart died young, suffering a fatal heart attack on Dec. 12, 1985, at the age of 47. So important was Stu's contribution to the band that, in 1989, they insisted that he be inducted into the Rock and Roll Hall of Fame with them.

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