A long time ago, Luna found a boy. The boy was lost and alone, covered in snot and tears. The boy, named Issac, followed the blue Alicorn and found a home in a castle full of ponies. A castle of two sisters. Lost but no longer alone. His story starts here, but begins much, much, later.

I really don't want to ruin the story for you too much. So, my apologies for the less than descriptive description. Guess you'll just have to read it to find out. Also, the first three chapters are the prologue. After that the style is more like the narratives we all know and love.

Also, that Alt-U tag is important. Twilight finding about Issac completely changes the "Mare in the Moon" opening, leading her to research into the Elements thus figuring out she'll return.