Grauer was born Anna-Margarita Grauer in Mexico City, Mexico, and is of Norwegian, Hungarian and German descent. She moved to Canada as a child, and was raised in Nelson, British Columbia. Grauer's mother worked as a caterer on the show MacGyver while raising Ona. Ona would later act alongside MacGyver star Richard Dean Anderson in Stargate SG-1. Her height is 5 ft 6 1⁄2 in (1.69 m).Grauer has appeared in a number of films such as House of the Dead and Deep Evil. She has also appeared in a number of television series besides the Stargate franchise, such as First Wave, The Net, Sliders, Freedom, Smallville, Tarzan, Andromeda, Archer and ABC-TV's re-imagined V series.Grauer has one son (b. 2004) and one daughter.