“American Idol” finalist David Cook may be missing one of his biggest supporters at the upcoming season finale: his brother.

As was revealed last month, Cook’s brother Adam has been fighting brain cancer for the last ten years. People magazine reports that though he was well enough to attend one episode, his condition will likely keep him from travelling back to Los Angeles again.

According to the his wife, Adam’s health is “A day-to-day thing. I can’t look at tomorrow. I have to look at today. If I start planning out and thinking about too much in the future, I can get overwhelmed in all the details. I have to concentrate on today.”

Cook will compete tonight against David Archuleta, with the champion being crowned tomorrow night.