Requested by CrystalSilverKnight and 8Suki8 . Hope you enjoy!

This story will take place when you and Leo were younger. Also, in this story, Leo is older than you.

Leo was locked up in his room and reading a book as always. His little sister, (Y/N), really wanted to play with him. It seemed like he never had time for her. (Y/N) played with Xander, Camilla, and her little sister Elise plenty of times, but never Leo because he always claimed he was "busy". However, this was all a ruse, as Leo knew that (Y/N) was not his sister by blood, and didn't want to get too attached to her and see her leave one day. Leo tried to ignore the little sounds of knocking at the door and tried to once again immerse himself in the book To Kill A Mockingbird.
"Leo, please open the door. I just want to spend time with you.", Leo heard his sister say. It almost sounded like she was going to cry.
Ugh, sometimes she's more annoying than Elise.
Leo opened the door, to see his adorable sisters face.
"Finally Leo! I never thought you'd open the door! Let's play!", (Y/N) said happily. (Y/N) followed Leo back to his desk.
"I'm not going to play with you (Y/N), but I can read to you, if you want.", Leo offered.
"Yes, yes, yes!!!!", (Y/N) said enthusiastically.
Leo sat down and pulled (Y/N) onto his lap. He put down To Kill A Mockingbird and picked up a book filled with fairy tales.
"Once upon a time...."
As Leo read, (Y/N) listened attentively, her big eyes wide with interest. They say time flies while you're having fun, and it's true. Before the two knew it, it was dark outside. (Y/N) was fighting sleep, but it was way past the little girls bedtime. Leo took notice of this and put her on his bed, then he got in next to her.
"Goodnight (Y/N).", Leo said as he kissed her forehead.

Fifteen years later.

(Y/N) was no longer the little girl Leo knew. Now she was a woman, his wife, and the mother of his children. (Y/N) had found out that she wasn't related to Xander, Camilla, Leo, and Elise by blood, but that didn't stop her bond with the nohrian royals. Leo had grown to fall in love with his little "sister" and after finding out that they weren't blood related, (Y/N) reciprocated his feelings. They were soon married and had two little boys, Forrest and Kana.
After putting the kids to bed, (Y/N), entered her and Leo's room to see Leo at the desk reading.
Some things really never change.
A small smile came to (Y/N)'s mouth as she remembered all the times she would want to play with Leo, but they would read instead. (Y/N) knocked on the wall.
"Finally Leo, I never thought you'd open the door. Let's play.", (Y/N) said with childish glee and a childish smile.
Leo looked up with a confused look on his face, but his face soon shown realization. He shared her small smile.
"I'm not going to play with you (Y/N), but I can read to you, if you want.". Leo said with a smirk.
"Yes, yes, yes!", (Y/N) said with more childish glee.
Leo picked up (Y/N) and set her on his lap. He had done this plenty of times, but he was just realizing how much (Y/N) had grown. And now that (Y/N) was older, Leo could keep on reading whatever he was reading.
(Y/N) soon fell asleep. Leo picked her up bridal style and laid her on their bed. He then got in next to her. "Goodnight (Y/N)", Leo said as he kissed her lips, and then her forehead.

Hope you enjoyed it!