Raising Sammy

Dean Winchester lost the love of his life and the mother to his daughter.
Now, 16 years later, Dean's been successful at leading that apple pie life with his daughter, Sammy.
Sam and Cas have kept evil away from them, while Dean raises her.
But Sammy is growing curious as to what her dad did before he was just a mechanic.
What happens when she discovers Dean's secrets and a letter her mother had written to her long ago?
Let's find out as we follow Dean and the others as they deal with a new threat.