It had been years since Celestia had given up her daughter, everypony knows her as Rainbow Dash but at first her names was Princess Rainbow. The white alicorn would of keep the rainbow mained pegasi but not being born an alicorn would of made life hard for Rainbow. It was not easy for Celestia to give up her baby, but she did it for the good of the Pegasus filly.
Celestia had watch her daughter from the background, she knew of her dream to become a Wonderbolt. Something she was quite prod of. Rainbow Dash had also done a sonic rainbom and is known as the fastest flyer, but that did not stop Celestia from imaging what life would of been like for her daughter if she had been born an alicorn and been Princess Rainbow. Celestia believed that Rainbow will still be the way she was today and want to be a Wonderbolt, but also that she might not have a lot of time to learn new moves. She also knew that Rainbow and Twilight would of become friends well before she went to Ponyvile.
In Celestia's mind she saw all the times she could of had with her daughter, from family fun days to reading bed time stories. She would take her around Equestria to meet knew ponys and learn knew ways of flying to help her fullfil her dream. She would also had her own trainer, one that would make her path even to becomeing a Wonderbolt a lot closer. Twilgiht and her would learn magic together and would go to Ponyvile where with the help of Applejack, Pinkie Pie, Fluttershy, and Rarity and return Nightmare Moon to Luna once more. Of course Rainbow would know that Luna was my sister and her aunt and would not be all that shocked when I called her sister.
But all those are nothing more but dreams, dreams that the white alicorn knew could never happen. True she loved her daughter with all her heart, but she knew this life was better for her. Even if she never knew that her mother was Princess Celestia, or that her half sister was Fluttershy. She would never know Luna was her aunt or her other family members.
But the mother still loved her daughter even if nopony, not even the blue pegasi mare knew that their beloved Princess Celestia was her mother.
This came out really well... I think its kind of cute ^^
