Luna Lovegood could be the main character. Her unique and dreamy nature would make for an interesting Mother's Day story. Her children might make her a crown of strange and beautiful magical creatures as a Mother's Day gift. And she could be spending the day teaching them about the magical creatures that most people don't believe in, all while having a very happy and peaceful Mother's Day.
It could be about a Harry Potter character who is a mother having an amazing Mother's Day. Maybe it's Molly Weasley's day filled with love from her family. Her children and husband could surprise her with a special breakfast, gifts like a new knitted sweater, and a day free from cooking. The story might show how much she means to the family in the context of this special day.
It could be Hermione. Since she values truth and knowledge so much, an oath of truth would be a significant concept for her. She might take the oath herself to prove the innocence of someone wrongly accused in the wizarding world, like Hagrid. And then use her wits and magical skills to fight against the false accusations.
Fans of both Harry Potter and the concept of the Dragon Mother would likely be interested. People who like to see crossovers between different fictional universes might also be into it.
There's also a possibility that it could be a minor character from the original series, like Neville Longbottom. He has grown a lot throughout the story. He might be the main character in this fanfiction, finally getting his own family after his heroics in the war. He could pass on his knowledge of Herbology to his children and create a family that is deeply involved in the study and protection of magical plants.
It could be a new character, perhaps a young witch or wizard who has just received their Hogwarts letter and then discovers this inheritance. This would be an exciting start to their magical journey.
Ron could be the main character in a Harry Potter polyjuice potion mishap fanfiction. Ron is known for his sometimes hasty decisions. He might be so eager to prove himself or get involved in some secret mission that he doesn't follow the potion - making instructions properly. This could lead to a mishap where he transforms into an unexpected person, and then has to navigate through the wizarding world in this new form, trying to hide his identity from his friends and family while also trying to reverse the effects of the potion.
In this fanfiction, Harry Potter is bound to be central. Given the title, his mother Lily Potter is a key figure. But other characters could also play significant roles. For instance, Dumbledore might be involved as he often guides Harry. And perhaps some of the antagonists like Draco Malfoy could also be part of the story, either in opposition to Harry's new - found gift or in some way related to the discovery or use of it.
It could be Harry himself. Maybe he's in a hurry to make the Polyjuice Potion for some important mission, like infiltrating the Death Eaters. But he messes it up and ends up looking like a really odd version of Voldemort, which causes all kinds of trouble and danger for him.
Maybe it's a new Slytherin character created specifically for the fanfiction. This character could be someone who has always admired Harry from afar and decides to take a chance on courting him. They might have different qualities from the typical Slytherins we know in the original books, being more open - minded and brave in their pursuit of Harry.
It could be a new student who has some unique magical ability related to transportation or control. They might use this ability to dominate the train in order to prove themselves to their new classmates.