Eileen Underwood is Zack's mother. She works as a successful doctor at the hospital. She is voiced by Vanessa Williams.
She has dark skin and black hair, with a purple band in it, she also has dark brown lips. She wears wire frame glasses and gold earrings. She wears a white doctor's coat over her purple scrubs. She has white shoes, and a stethoscope around her neck.
In Worked Day her son's class came to the hospital, where Murphy's law takes effect and turns an MRI into a super magnet that attracts all metal the city.
In Murphy's Lard she is seen in a flashback with her husband and son in a pontoon in the Saskatchewan river where Zack freaks out and jumps out of the boat when a fish lands by him.