Derek Fisher's daughter, Tatum, was born with a rare eye condition called aniridia. Aniridia is a congenital disorder that results in the complete or partial absence of the iris (the colored part of the eye). This can cause serious vision problems and may require surgery to correct.
Tatum has undergone several surgeries to improve her vision, including one that removed her cornea and replaced it with artificial tissue. She also wears special contact lenses that help her see better. Despite all of these challenges, Tatum is a happy and thriving young girl.