Sam and Mary

Sam Winchester and Mary Winchester have a mother son relationship. Although, Mary died early in Sam's life, so he didn't know much about her, or what a mother's love is. Sam does care for Mary though, and misses her.

Background
Sam is Mary's second born son, and unfortunately, didn't get to be there in his life. Mary died on Sam's 6 month birthday, in his nursery. She died trying to protect Sam from the yellow eyed demon.