For many years the people who lived on the doomed surface tried in vain to beat back the poisonous slimes and molds that were taking over their homes. They failed. Finally the decision was made to flee in the only direction they could; straight up. Great magics were used to create the flying ships and floating islands that would be the salvation and the new homes for the sentient people of Golarion but this was a desperate move by desperate people and while the magical powers were being harnessed many more lives were threatened.
It was this plight that moved the heavenly angels of the Celestial Sphere and they came to aid the pollution beseiged people. They helped to hold off the slime from the last few uncorrupted places, aided the magic that was raising them to the skies, and in the end helped to swoop down and carry trapped peoples to the rising islands.
Whether because of the suffusion of divine energies or because of more direct contact, many Aasimars came to be born among the refugees from the surface as they forged a new path in the skies. Eleanis is of this line. Her light blue hair a mark of her more than human origin. Almost more wondrous is a tattoo of a sparrow in flight over a curved branch that she was born with on her right shoulder. Taken as a physical manifestation of their new lives in the sky and their salvation from the doomed land below Eleanis is raised with love and affection from all of the members of her family and even her island. She returns this love and it is an easy transition for her to join the clergy of Shelyn where she thrives. Her tattoo glows the first day she enters the surface and does so now every time that she calls on her goddess for aid.