Nina frowned. "But you weren't born with it," she said, more to herself than to Tony. She touched his hair again, considering. She could try moving color, but-- she wondered if that would result in just bleaching a different part of his head. Better, perhaps, to recreate it.

She turned to her tailoring kit and searched for a color that would match Tony's dark hair. She held each up to the light until she found one that satisfied her.

"If it's become genetic, somehow, whatever solution I offer will be temporary. Longer and better-looking than any dye job - your hair will even grow that way for a while - but eventually whatever genetic change has happened will re-assert itself. I only know of one Grisha that has the power to create permanent physical change in a person. And Genya isn't here."

Nina wasn't a tailor, she just knew how to do it and was a fair hand at it. Genya was had a talent for it beyond measure. She opened the vial of dry pigment and tapped it out on top of Tony's head. Then she ran his fingers through his hair, the part that had turned blonde, and carefully worked to make sure every strand accepted its new pigment.