Why...sister?

"Come on Tia!" Little Luna shouted

"He he, coming Luna! Ha ha, I'm gonna get you!" Celestia yelled back to her running little sister. The two were unseperable ever since the birth of Luna. Tia found herself loving more and more being a big sister, when she first heard of the new little princess filly, she thought it was nothing but a terrible, horrible idea. She thought her pure hatred for the unborn filly was long lasting, but when Luna arrived Tia felt happier, like her mother had risen the sun just to bless the baby with the taste of sun. Luna started dashing for the hilltop, her little hooves carrying her, while her little wings fluttered, lifting her a few centimeters off the ground. Tia looked in astonishment. 'I'm flying Tia! I'm really flying!" Luna said bursting into a bright smile, almost as bright as the rising moon.

'Wow! Go Luna!" Tia cheered on her sister. Then sadly she plummeted to the ground. Although she was only a few steps off the ground, it was about 300 feet to Luna, being only 3 years old. Tia flew quickly to her little sister, whose lip began to quiver as tears bulged in her eyes. Luna began crying at the top of her lungs. "TIA! TIA! GET MOMMY!" Luna cried as Tia grabbed her favorite toy and went over to comfort her. 'Shh, it is okay Lulu, I'm here" Tia said comfortably then continued "We better get you inside, and get you checked out."

"Thanks Tia. You're the best." Luna said sniffling

"I couldn't be if it weren't for you. I love you Lulu."

Luna smiled shyly because she had a little trouble saying the l-word. She just hugged her sister, tightly.

"Hang on." Tia said as she flew carefully to back to their home, making sure Luna's grip held.

"Looks like she isn't hurt, good job getting her back here safely Celestia." their dad Moonlight Night said to Tia.

"Well, I didn't want anything to happen to her. She is my little sister after all." Tia said walking over to Luna. She wrapped her wing around a still frightened Luna, hugging her tightly, into and embrace that made the sisterly connect between them stronger.

"Well, you two need to get to bed. Good night girls, I love you." Their father said, opening the door for Tia, who was holding Lulu, to walk out of.

"Nighty night daddy!" Luna said waving good night to her loving father. He waved back. The two walked down the corridor and into their bedroom, where Tia laid Lulu down and tucked her in. She then crawled into bed, but before her eyes grew heavy, and soon would close, she felt a tight embrace around her, it was Luna. Then she sleepily said "Good night Tia, I love you." Celestia smiled and returned the hug, then she fell asleep.