Okay, I'm writing another post today. It started when a boy asked for prayer for his cousin to be healed of cancer lest she die in three months. The answer: "You know God can heal that. You just gotta have faith."
Ugh. That's the last thing you need to say to that kid. I think there is nothing that discourages faith more than saying someone can be healed with faith and then they die anyway. It's like, was my faith not enough? Believe me, faith has nothing to do with it. It does, but God still sovereignly decides what to do with a person, and he knows what he's doing.
That doesn't mean I still don't grieve or ache. But when someone I pray for does not heal, it does not mean I didn't have enough faith. In fact, that may be the answer; God heals them at home. And when he does, he's not evil, careless, or impotent. He's God and he knows what he's doing. I trust him to run this planet better than me.
So pray for your loved ones, for both healing and believing, but know that the result is only in God's hands.