Maybe it's the child of one of his friends or allies. For example, it could be the baby of Ron and Hermione. Harry would then be taking care of the baby out of loyalty and friendship.
In this fanfiction, perhaps Harry could struggle at first with the basic tasks like feeding and changing the baby. He might make mistakes but learn quickly.
Harry might first try to figure out what's wrong. If the baby is hungry, he'll quickly get a bottle. If it's a wet diaper, he'll change it. Sometimes, he just holds the baby close and rocks it gently, humming a little tune. He doesn't get frustrated easily because he really cares about the baby.
One possible plot could be that Harry discovers a time - traveling accident has brought baby Snape to his present. Harry, being the kind - hearted person he is, takes it upon himself to care for the baby. He has to figure out how to feed the baby, keep him clean and comfortable. Maybe he also has to protect baby Snape from any threats in the wizarding world that might target Snape even as a baby.
A heartwarming moment could be when Harry takes the baby out for a walk. He pushes the stroller carefully, talking to the baby about all the things they see around them, like the colorful flowers and the friendly squirrels. And at night, when the baby has a nightmare and Harry stays up all night comforting it. He rocks the baby gently and whispers soothing words until the baby calms down and falls back asleep.
One possibility could be that Draco is forced into taking care of Harry due to some magical circumstances. Maybe there's a spell gone wrong that makes it his responsibility. He initially resents it but as he spends time with baby Harry, he starts to see the innocence in him and develops a soft spot.
Well, Harry might use his magic to make the baby laugh. For example, he could turn the baby's rattle into a little magical creature that dances around. He'd probably also be very protective, like how he was with his friends at Hogwarts.
Well, clearly Harry is one of the main characters as he is the one taking care of the baby cousin. The baby cousin is also a main character, even if it's a young and not fully developed character yet.
Harry is known for his kindness and loyalty. So, he would take care of Draco with a lot of patience. He would probably stay up all night if Draco was fussy, just to make sure he was okay. His protective nature would also mean he'd keep Draco safe from any harm, whether it's from other wizards or just from the general dangers in the wizarding world.
Well, in such a fanfiction, it could greatly change the storyline. Snape is often portrayed as a complex and somewhat bitter character in the original story. But if he takes care of baby Harry, he might develop a different kind of bond with him. Maybe he'd become more protective and less resentful towards Harry as he watches him grow. This could lead to a completely different dynamic between Snape and the other characters too, like Dumbledore. He might not be as secretive from Dumbledore about his feelings for Harry.