|Episode(s)||7.03 The Girl Next Door|
Jacob and his mother Amy Pond are kitsunes. She is working as a mortician which is where she obtains the brains and pituitary glands they feed on. However when he becomes sick, and only fresh brains will heal him, Amy kills three people to save him.
Sam sees details of the killings in a local paper, and examines the body of the latest victim - a drug dealer who has had part of his brain removed.
Sam tracks Amy, and she pleads her case with him - this was an extraordinary situation, and she is trying to live a normal life. Remembering that she killed her mother to save him, Sam lets her live.
After Dean catches up with him, Sam reveals the whole story. Later unbeknownst to Sam, Dean tracks Amy down and kills her. Jacob witnesses the murder. Dean tells him if he ever kills anyone, he'll come after him. Jacob replies "The only person I'm going to kill - is you."