Talk:Episodes, films, and shorts/@comment-5288784-20160327161932

My new personal headcanon:

The ancient alicorns were a highly magical race living in a land called "Canterlot". In their search of knowledge they've unleashed a curse upon their race that caused the majority of their race to wither and die. Two sisters were somehow saved, but even then they could be rendered infertile. By the time Equestria was founded, Celestia and Luna were already among the last surviving members of their race. Currently we have knowledge of three alicorns that survived the apocalypse, with only two of them being currently in a relative good condition and the third one shattered, with two ponies on a mission to piece her back together.

Perhaps one or more of them did try to mother a foal, but even if she succeeded, it was never an alicorn. The newborn would only be able to inherit the pony magic from the father side, and a non-alicorn father would only be able to give one of the three kinds of magic at a single time*, whereas an alicorn requires three to be developed.

By the time Princess Celestia discovered a way to grant alicornhood to other ponies, she had already abandoned hopes of restoring the alicorn race. Perhaps this is for the better, since we avoided the temptation of giving alicorn powers to undeserving ponies and controlled breeding.

The birth of Flurry Heart is the first alicorn birth since the apocalypse. Is it a new hope for the alicorns, or perhaps a unique event that can't be repeated regularly enough? Only time will tell.

* Usually the father and the mother will give the magic appropriate to their own race. If the family line was "impure", there will be residues of other magic of other races, but only one of them will be dominant enough to determine the race. In rare cases those residues can overpower the magic from the race of a parent, as seen in Cake Babies. Only an alicorn body can will three kinds of magic to coexist peacefully.