Who is Miriam from Valley of the Dolls and what is their importance?

Miriam is Tony Polar's manager, sister, and foster mother. She is fourteen years older than her half-brother, and she raised him alone, in poverty, after their mother's death. Miriam is in complete control of Tony's image and his career. She resists his marriage to Jennifer because she does not know if Jennifer can be trusted to keep his secret. She later tells Jennifer the truth about Tony's condition, so Jennifer knows what the future could be like for her unborn child.