Nair Wildfire is technically Rian Wildfire's sister. She is genetically identical to him, only female, and even looks just like him. Nair is mentioned briefly in Absolution from The Concourse to Victory, and was also the focus of a cut story.
Nair was created to be the leader of an army of genetically-enhanced Rian-clones. If I'm ever hurting for ideas, this is a good story to revisit.