Sad news from the east

My paternal uncle, the father of my dear cousins out in Boston, is gravely hurt and has been in the hospital for the past week. He was supposed to have surgery this morning, but at 6 a.m. today, his family got a call that their dad was back in the ICU, on a respirator, and they'd best all get down there as soon as possible. We'd all been praying daily for his recovery, and what a crushing setback we've gotten instead. Again, I'm left wondering (childishly, I'm sure) about the usefulness of prayer in doing anything besides making people feel like they're doing something at the time they're praying. Of course, I continue to pray, and in faith, but there's this weird little stream of thought going at the same time that says "pray all you want; it won't matter. What's going to happen is what's going to happen, and your prayers will have nothing to do with it." Maybe that's why a lot of people say we should pray for God's will to happen, and for ourselves to accept it with strength and with grace. I just want my uncle to pull through, so my aunt can have her husband and my cousins can have their dad for a few years longer.