In 'the song remains the same' Anna and Uriel try to kill Mary so Sam wouldn't have been born. Michael rescues them and erases their memories but later we see a pregnant Mary telling her baby, Dean, that angels are watching over him.
Mary used to sing "Hey Jude" to Dean and she made him tomato soup with rice when he was sick.
Mary named Sam and Dean after her parents Samuel and Deanna.
I love how strong and kickass Mary was and I just love her. She loves her children and didn't want any of this to happen to them.
Mary never wanted for her children to have the life she had. She didn't want Sam and Dean to grow up like hunters and she would do anything to stop that from happening. That makes me very sad because her death actually turned Sam and Dean into Hunters.