Hilary Erhard Duff was born on September 28, 1987 in Houston, Texas, to Susan Colleen (née Cobb), a homemaker, and Robert Erhard Duff, a partner in a chain of convenience stores. Duff has an elder sister, Haylie, who is also an actress and singer.

Her mother encouraged her to enroll in acting classes alongside Haylie. Both girls won roles in local theatre productions. At the ages of six and eight, the two sisters participated in a BalletMet Columbus production of The Nutcracker Suite in San Antonio.

Hilary Duff's Family Tree