Disclaimer: I don't own Harry Potter or Lord of the Rings. I don't even own Stella, only Éostrǽl.
It was a perfectly quiet morning in Edoras. Well, almost. Suddenly you could here a young girls laughter. The voice belonged to Éostrǽl and she was running away from her older brother. She actually got to the stables before Éomer caught her. He lifted her up and carried her back to Meduseld and to her room where Éowyn was already waiting for her. She smiled softly at her little sister for she knew exactly how she felt. A few years ago they had been trying to avoid going to balls together but Éowyn was 15 now and she couldn't do things like that anymore. Éomer looked at both of them knowingly, he was very aware of his little sisters feelings towards balls but they were the princesses of Rohan, they had to go. He left them with an apologetic look on his face. He loved these girls. They were the only real family he had left and he would never let anything harm them, well except making them attending balls.
Éowyn smiled at her sister again. "I know you do not want to go and neither do I. I would very much prefer to go for a ride but that is not a possibility tonight so we should just get ready. The sooner it starts the sooner it will be over."
"I liked it better when you were on my side.", Éostrǽl said, trying to act hurt.
"I am on your side, you know that." And with these words she picked her little sister up and carried her to the bathroom.
Meduseld was bursting with people that night and Éostrǽl had to greet every single one of them. Some days she just hated being a princess, on others she loved it. But she definitely was no ordinary princess, not even an ordinary girl for that matter. She didn't care about balls, pretty dresses or any of that stuff. She preferred to be on horseback for hours or to practice her fighting skills with her siblings, she never wore dresses when she didn't had to and she got dirty a lot. Some people say she was that way because she basically grew up without parents, they had died when she was only three years old. After that she was raised by her uncle, always in the company of either Éomer or Théodred, or both. The only important female in her life was Éowyn and she had been seven when their parents died so she never got that much female influence either. But what ever the reasons were everybody agreed that Éostrǽl of Rohan was not average, not at all.
She was talking to Éowyn when she noticed a strange man looking at her. He had long white hair and an even longer beard, and he looked incredibly old. She stared back at him for a moment, then turned to her sister again. "Éowyn, who is that man over there? The one with the long hair and beard?"
"I do not know. I have never seen him before. We should ask Éomer." And so the two of them went to find their brother but before they did the old man got in their way. "Excuse me, my name is Albus Dumbledore and I need to have a word with you, Miss Éostrǽl, in fact it would be quite good if I could talk to all three of you."
"Why?" Éostrǽl tended to forget her manners from time to time. Éowyn nudged her in the ribs and then said: "Of course you can have a word with us, we only need to find Éomer."
"That will not be a necessary.", said the aforementioned who had suddenly turned up behind his sisters.
"Marvellous.", Dumbledore exclaimed. "Can we speak in private?"
"Follow me." Éomer said and led them to an empty room away from the ball. As soon as he had closed the door behind him Dumbledore started to speak: "I come from a different world, it's called Earth and it's a parallel world to Middel-Earth. Furthermore I am a wizard and I am not like the wizards you know here." He went on, explaining everything about the Wizarding World and Hogwarts to them. When he finished all three looked at him amazed. Éostrǽl was the first to regain the ability of talking. "Why are you telling us all of this?"
"Because my dear you are just like me. You are a witch and I would be delighted if you would come to Hogwarts so we can teach you how to use magic."
"I am a witch?", she asked astonished.
"Yes dear you are. Haven't you ever done inexplicable things?"
She nodded, not being able to talk yet, which was a rare thing for her. When she found her voice again she asked what she had to do.
"Well, you have to buy your school-things but I will help you with that and on the 1st of September I will pick you up here and bring you to the Hogwarts Express which takes all the students to the school."
The three siblings kept on asking Dumbledore questions about this Wizarding World, Hogwarts and if Éostrǽl really could go to a school in a completely different world and if she actually wanted to go. But in the end they settled a day for Dumbledore to take her to Diagon Alley.