Unknown. Celebrated December 5.
Luzo Komaki, then-32-year-old-bachelor and lonely pear merchant was heading home to a nearby village after having completed a delivery to the Village of Hidden Mists. Ecstatic to have earned more coin from this yield than his usual margin, he drove his oxen at a slower pace than usual in order to enjoy the scenery. Due to this happy coincidence, the man's ears caught wind of infant wailing at the roadside over the rumble and tumble of his wagon's wheels. Upon investigation, he discovered an infant girl in a basket with a small, green blanket wrapped about her tiny frame. After spending the remainder of his day back in Kirigakure searching for her parents, Luzo decided to adopt the child, reasoning that she had been abandoned for one reason or another. Because he found nothing to indicate it, he spent his long trip home pondering what name to bestow upon the girl, and eventually decided to name her after his fondly-remembered grandmother.
Elsewhere, a pair of Kirigakure missing-nin embraced each other, wordlessly mourning their misfortune and loss. Having made the mistake of bringing a child into the world, they were forced to decide between raising a child on the run, or simply abandoning her in the hopes of granting her an easier life outside of the jaws of hunter-nin. Bearing their regrets with sorrow, they chose the latter.
This child's life was relatively lively and happy; Rina Komaki played, learned, and loved her dear father, who spared no effort to make his daughter's life as comfortable as he could. At an early age he instilled in her the importance of education and cleverness, which didn't take too much effort; Rina turned out to be very malleable indeed, taking well to his suggestions and orders alike. She didn't much mind the bit of teasing she received from some of the crueler children, who'd poke fun at her for lacking a mother and furthermore insist that she'd been adopted, using her differing features from her father as evidence. It took eight years before Rina had deduced her adoption, and another three before she set out for Kirigakure to become a ninja; this particular choice was fueled by a desire to find her parents. To find her parents, she would need to travel the world. To travel the world, she would require strength. To earn strength, she would need to become a ninja. This new goal was not born of any hatred or disappointment in her father; rather, Rina simply felt an immense compulsion to discover her origin.
As a ninja, Rina proved to be excellent at being average in almost all respects other than her desire to learn. However, desire isn't necessarily enough; she simply lacked in raw talent. Over the course of seven years, her improvement since graduation from the Ninja Academy had proven to be minimal. Because of these many years of crushing mediocrity, her attitude shifted from powerful determination to a less-enthusiastic, lackadaisical composure. Eventually, she decided that time was up; the hour had come to embark, whether she was ready or not. With a resignation that raised few eyebrows and a tearful goodbye to her dear foster father, Rina set off to discover what lay beyond her homeland.