"There's a little of every artist in their work"."[src]
Stelline was born on June 10, 2021, the daughter of former Blade Runner Rick Deckard and Rachael, a Nexus replicant model, making her the first replicant-born child. In order to protect his daughter and partner, Deckard left them in the care of the Replicant Freedom Movement, specifically Sapper Morton and Freysa. Furthermore, he scrambled the birth records of his daughter, making it seem that the pregnancy produced twins, a boy and a girl with identical DNA, and that the girl died young of a genetic disorder.
By 2049, Stelline was employed by the Wallace Corporation and had to be quarantined due to her health. For her work she was confined to a dome where, she could use a "memory orb" device to construct replicant memories to structure personalities. She manipulated these via holograms that she could interact with, and would presumably ship them off to Wallace. She claimed to love birthday parties, often creating memories based on them.
On July 4, she was visited by Nexus-9 Blade Runner K, who asked her to determine the authenticity of a childhood memory of his. She examined the memory, which emotionally moved her, and confirmed that it was indeed real.
Freysa soon revealed to K that Stelline was the daughter of Deckard and Rachael. K took Deckard to Stelline's lab as she interacted with a snowfall hologram. She did not recognize him, but Deckard affectionately placed his open hand on the window.
She was known to wear white dresses and go around barefoot.
She appeared to be cheerful, good-natured, and probably a little eccentric, given her penchant for going barefoot and her habit of working on holograms while talking to people.