Billie Proudman (played by Kat Stewart) is Nina's older sister. She works in the family real estate company, and is married to musician Rick.
Growing up, Billie was the black sheep of the Proudman family, and while still maintaining her outgoing personality, shes determined to put those days behind her and make something of her life.
Billie is an extrovert who is incapable of lying; shes straight up and tells it like it is. Her adventurous and wild demeanour aside, she is soft at heart and will do anything to protect her loved ones.
Unfortunately for Billie, she is unable to have children of her own, so season four will see her delve into her professional career.