Nikki the Lynx was the daughter of Dr. Ellidy. Little about her is known other than that she passed away many years ago, and the Doctor's attempt to digitally replicate her personality led to the creation of Nicole the Holo-Lynx.
Nikki was the apple of her father's eye, and they enjoyed many experiences together, including visits to a Chao Garden, the Emerald Coast, and Empire City, where Nikki took first place in a science fair. After learning of her father's work on the Mobotropolis Grand Archive, which was designed as a government program, Nikki suggested making it available to the public. Sadly, Nikki subsequently fell victim to a debilitating condition and Ellidy attempted to save her life via the Digitizer when Professor Charles the Hedgehog failed to complete his Roboticizer on time. He did so by mapping Nikki's neural pathways into the computer, to later attempt more complex copying. However, this attempt failed to save Nikki and instead contributed to Nicole's development, leaving Ellidy bitter and harboring negative feelings towards his A.I. creation. He later created a shrine to his daughter on Isolated Island, which was later discovered by Sally Acorn. This prompted Ellidy to reveal what had happened to her, something that Nicole would also discover while battling the villainous Phage. Ellidy would later lament that Nikki and Sally had never met while Nicole would recognize the loss of the young Lynx as contributing to her own development into a feeling being. (SU: #73, #74)
Nikki appears to have been a kind, happy child who seems to have shared some of her father's aptitude for science.
Nikki appears to have shared her father's fur color, and like him had a triangular marking on her face that ran from the tip of her nose up between her eyelids. She had blue eyes and wore glasses, and apparently favored an outfit with a blue decoration on the collar resembling a flower.
- Nikki shares her name - though not her species or gender - with a character from the Sonic the Hedgehog manga series published by Shogakukann. This Nikki was Sonic the Hedgehog's mild-mannered alter-ego, who transformed into Sonic under duress and was unaware that the change took place.
- Nikki may also be an allusion to an abandoned concept from the Saturday Morning Sonic the Hedgehog cartoon, where NICOLE was actually a living being who was transformed into the computer by Dr. Robotnik.
- Nikki is similar to Maria Robotnik, in that they are both young females who were dying from incurable diseases and whose parental figures attempted to save their lives through science which resulted in creating an artificial being, but they ended up dying anyway, causing the parental figures to become sad and bitter.