There was an amazing zombie apocalypse mpreg where Dean was pregnant and gave birth to a boy. Dean did not grow attached to the baby until one day the baby became so sick he thought it would die.

Fast foreward and the baby is now a toddler. Dean and the family (I still have no idea what the pairing is in this fic) settle down in an abandoned house. Zombies attack and bite the toddler, and there's a heartwrenching wait to see if the boy survives (not sure if he does).

Any ideas? I'm like 97% sure I have the right fandom/characters.

Eta: FOUND. Dean is actually Jensen in the story I'm looking for. Oop.