The movie Broken Hill has some basis in reality. While it might not be a verbatim account of a specific true story, it incorporates themes and scenarios that could have occurred in real life.
It's hard to say for sure. There are some reports and observations that suggest elephants might have certain behaviors related to the death of their own kind, but it's not clear if it can be classified as a 'funeral' in the traditional sense.
Sirius Black could also be part of it. He was Harry's godfather. He might have escaped from Azkaban earlier in this fanfic. He teams up with the Potters to rescue Harry. He could be the one who scouts out the Dursleys' house before the actual rescue operation, using his skills as an Animagus to stay hidden.
It could also be that the Potters are under some sort of magical influence or curse. In the fan fiction world, there could be a dark force at play that makes them see the twins as more important. This force might be manipulating their emotions and perception, leading to the neglect of Harry.
One possible reason could be that the twins might have some special abilities or circumstances that draw the Potters' attention more. Maybe they are more outgoing and seem to need more immediate care or guidance. Another reason could be that there is some sort of miscommunication or misunderstanding within the family. For example, the Potters might think Harry is more self - sufficient when in fact he also needs their love and attention.
Perhaps there's a plot against Harry by some dark forces, and the Potters believe that only they can protect him properly. They might think that the people who have been taking care of Harry so far are not equipped to handle the new and more dangerous threats. Also, it could be that the afterlife in the wizarding world has some rules or opportunities that allow them to try and get Harry back into their family fold. They could have been given a second chance, so to speak, and are eager to take it.
Harry might become withdrawn and introverted. Feeling unloved and unwanted, he could start to keep to himself more, spending time alone in his room or exploring the grounds of their home alone, trying to make sense of why his parents seem to favor the twins.
He might become withdrawn. Feeling unloved and ignored, Harry could start to keep to himself more, not sharing his thoughts and feelings with his family. He may also become resentful towards the twins, seeing them as the cause of his being neglected, even if it's not entirely their fault.
One common theme is self - discovery. Female potters often start out not fully aware of their powers or potential, and the story is about them finding out who they really are. For example, they might learn about their family history that has been hidden from them and realize their true place in the wizarding world.