Adam Cook, 36, a lawyer, died early Sunday morning after an 11-year struggle with the disease, which had spread to his spine. He leaves behind his wife, Kendra, and their children.
David made the announcement Sunday morning at the 12th Annual Race for Hope 5K run/walk in Washington, D.C., benefiting finding a cure for brain cancer. The "Light On" rocker was the event's honorary chairman and his team raised more the $97,000 for the cause.
The brothers had one of A.I.'s most memorable, tear-worthy moments ever, when Adam sat in the audience in April 2008 and watched David perform his rendition of Mariah Carey's "Always Be My Baby."
Residents of their hometown in Terre Haute, Ind., raised $45,000 so that Adam could be flown in with the proper medical care.
(Originally published May 3, 2009, at 10:45 a.m. PT)
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