Ikari Uchiha of the main Uchiha family was born a freak of nature with fully active Mangekyo Sharingan.
It came as something of a shock to the whole clan when the news was reported from the wet nurses, however any excitement and awe at the discovery was sidelined when the mother fell into critical condition.
It was said that Tajima Uchiha had rushed into the clan's infirmary without a word or care about appearances to come to his wife's side. It may not always show, but the Uchiha's were a clan that loved the most.
This was why, when it was reported that Mrs. Uchiha would die, no one had the courage to approach Tajima's still form.
Pale and rasping for breath, the one request Mrs. Uchiha had made was to hold onto her newborn child up until the very moment she died…and that's when it happened.
A pair of Mangekyo began to spin and wind, drawing in an excess amount of chakra that converged over Mrs. Uchiha's form.
Much to Tajima's shock, his deceased wife returned to the land of the living, healthy as can be. The child in comparison fell unconscious from over fatigue.
After much debate and deliberation, the clan physicians came to the stark conclusion that Ikari Uchiha would be bedridden for the majority of her life. The toll of a constantly active Mangekyo Sharigan was unimaginable, but more than that, the hypothesised ability of her eyes quickly became designated as a clan secret of the highest order.
Be that as it may, it didn't take long to understand certain drawbacks.
Five years. It had already passed five years, and not once had Ikari Uchiha ever been able to recognize her own mother.
In bringing back life to that which was dead, the memories of that person can no longer exist in Ikari Uchiha's mind. Hence, it was an ability that could only be used once, but at a terrible cost.
…Because sometimes it hurts more to be forgotten than to be alive.