Nat is a house-elf who serves the Dearborn family.
In May of 2010, Darla Dearborn compelled Nat to take her and Innocence Pritchard to the gateway cave below the Charmbridge Academy. Darla was nearly stopped by Alexandra Quick, who hit Nat with a Stunning Spell before dueling Dearborn, who hit Quick with a poorly-cast Killing Curse.
With Quick unconscious, Nat was forced by Darla to send her and Innocence to the Lands Below. When Quick regained consciousness, she persuaded Nat to send her Below as well in order for her to rescue Innocence and Darla.
Mary mentioned Nat again to Alex in October of 2010.