Supernatural - The Sister

Basically, just a couple years afyer Mary died, John had a daughter, Allison (Alli). He thought the safer place would be with Sam and Dean before they could go on their own hunts by themselve. When Sam left to collage, Alli went off in her own because her and John didn't get along when it came to hunts. She met a boy, who was also a hunter. They dated for a few years until he was killed. When she found out that John had also died, she thought everything had fallen apart. She needed to see her brother, alothough she didn't get along well with Sam. So yeah