David Cook

American Idol Season 7 winner David Cook opened up about the death of his brother, Adam, and vowed to continue his fight for others battling cancer.

Cook thanked his fans for their support on his official website, and explained why he wasn't with his brother when he died. Cook had flown into Washington, D.C., to participate in the 12th Annual Race for Hope 5K on Sunday.

"I decided to run in the race, despite all of this, for two reasons," Cook wrote. "First, my brother never wanted his illness to affect others... So, with that wish in mind, I ran and was involved with the event as an homage to him... Secondly, there are many people who are still battling, and by running and sharing my brother's story, I hope that it offers those still fighting that much more resolve to not succumb to this wretched disease."

Season 7 Idol runner-up David Archuleta applauded the way Cook is handling the death. "I know they had been struggling with it for a while, so my heart really goes out to them," Archuleta told Us. "It's so admirable the way he's handling it though, and it's amazing to see him there as an example for millions of other people who have also been affected the same way he and his family have."

Adam Cook, 37, battled brain cancer for 11 years before his death on May 2, and David gave extra thanks to those who have donated money to brain-cancer research in response to his brother's death. "I take it as affirmation that my brother was the great man that I knew, and whose ideals I constantly try to uphold in myself," he said. "It is with those ideals in tow that I vow to continue to speak out in hopes of raising whatever necessary to help eliminate cancer entirely."

In that fighting spirit, Cook's tour will go on as scheduled, with only a May 6 appearance in Toledo, Ohio, being canceled.

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