Losing it all

Jack, a lost spirit, had met with three teenagers: Hiccup, Rapunzel, and Merida. After being ignored and walked through for most of his early years of a spirit, Jack had found a trio which would acompany him for short years. He then lost contact with them. Over time, Jack left them with, leaving them on their own to grow up, his heart filled with regret and confusion
What happens now, Jack?