The daughter of Joan and Harry Seltzer, Jill grew up in St. Louis County with older brother Garry and younger sister Joy. Jill’s dad ran a salvage yard with his father until shortly after Jill’s grandfather’s death, and then sold cars for Weber Chevrolet. Her mom worked as a clinical audiologist.
Jill is a graduate of Parkway North High School and the University of Missouri in Columbia. She took graduate coursework and earned a teaching certificate from the University of Missouri at St. Louis. She briefly taught, then spent her career as a small business executive.
Jill has been married to Mark Schupp for 32 years and they have two sons, Brandon and Alex. While volunteering at her sons’ school, Jill became motivated and was encouraged to run for the Ladue School Board, and thus began her work as an elected official.