Songs for a Remembrance Service?

Hi there, I've been asked to sing and play Piano/Guitar at a Remembrance service in September for families of Cancer victims. Which I'm really honoured to be asked but I'm completely stuck for ideas. Trying to think outside the box and do something a bit special for them. Had thought about "I remember" by Damien Rice (a bit too long at 10 minutes sadly lol), "If you see her, say hello" by Bob Dylan but to be honest I'm not too sure. I'm not looking for anything that has been overplayed like "When September ends" by Green Day. I just want something soulful and meaningful. All replies will be greatly appreciated. Thanks for looking guys and gals!