Lyric discussion by btrue89 

Cover art for Baby Blue lyrics by Dave Matthews Band

I agree that it's not specifically about LeRoi or specifically about his sister. It's about losing someone and saying goodbye. He obviously wrote this with both of their deaths hanging over his head, but I don't think you can say they are about either individually. Terrific song though. He's got one hell of a voice. I like this, Time Bomb, and Lying In the Hands of God.