In some fanfictions, magic might be used to bring them back. For example, a powerful time - turning spell could be involved, allowing them to be retrieved from the past before their deaths. Another way could be through some sort of deal with dark forces, although this would likely have many negative consequences.
They could use magic spells that are long forgotten. Maybe they find a way to communicate with Harry through his dreams, guiding him to a place where they can be reunited.
One common plotline is the search for a way to reverse the death spell. Harry and his friends might go on a quest to find rare ingredients or spells. Another is that there could be a prophecy about Harry being the one to bring his parents back, which drives the story forward. Also, there could be conflicts with the Ministry of Magic, as they might oppose any attempts to bring back the dead.
He might face opposition from the wizarding authorities. Resurrecting the dead is generally not allowed in the wizarding world, so he could get into a lot of trouble.
Hermione and Ron are usually quite common. Since they are Harry's best friends, they would be involved in the story when Harry's parents return. They might be curious about his parents, and also help Harry and his parents adjust to the current situation.
One possible reason could be that he might feel abandoned. Growing up without them, he could resent the fact that they left him an orphan. He might think that if they were really so great, they would have found a way to survive and be there for him.
One possibility could be that Harry is the son of a powerful but mysterious wizard and a muggle - born witch who had to give him up for some reason. Maybe his real father was a dark wizard who was hunted down, and his mother was a brave witch who wanted to protect Harry from that dark legacy.
Well, it could be two powerful Aurors who were thought to be dead but were actually in hiding. They might have been fighting against Voldemort's forces and had to disappear to protect their family. Maybe they were friends with James and Lily Potter and got caught up in the same battle that led to the Potters' death.
In some fanfictions, Harry might use extremely powerful and ancient magic. Maybe he discovers a long - lost spell during his adventures that has the power to reverse death. For example, he could find a spell hidden in a forgotten corner of the Hogwarts library that was created by a powerful wizard in the past but was deemed too dangerous to be used.
One possible reason could be a misunderstanding. Maybe he discovers some secrets about his parents that he misinterprets. For example, if he finds out they were involved in some dangerous or morally ambiguous activities in their youth that he doesn't fully understand at first.
One possible reason could be that he discovers some long - hidden family secrets that make him question his parents' actions or decisions. Maybe he finds out about some dark deeds in their past that he can't overlook.