Not much is known at all about Uru, mother of Mufasa and Scar. Not even what she looks like. She is never featured, only mentioned. Fans suggest she would have a coat similar to Scar, as to allow that darker coat gene to pass from Uru to Scar. Also suggested is that she would have had green and yellow eyes.
In A Tale Of Two Brothers, it is mentioned that Uru went to search for water, because the Pride Lands were suffering a terrible drought. Other than that, not much is known about Uru.