Zelda Rubinstein was born on May 28, 1933, in Pittsburgh, Pennsylvania, to Jewish immigrant parents from Poland, Dolores and George Rubinstein. She was the youngest of three children and the only short-statured person in her family.

Zelda Rubinstein did not become comfortable with her short stature until she was an adult. She stood 4 feet 3 inches tall due to a deficiency of the anterior pituitary gland, which produces growth hormone.

Zelda Rubinstein won a scholarship to the University of Pittsburgh, where she earned her bachelor's degree in bacteriology and became a sister of the national sorority Phi Sigma Sigma. She moved to Berkeley, California, at the age of 25, studied at the University of California, Berkeley, and worked as a medical lab technician at blood banks.

In 1978, she decided to pursue an acting career. She studied acting at the University of California and made her movie debut as one of the little people in the Chevy Chase slapstick comedy "Under the Rainbow" (1981).

Her role as the eccentric medium Tangina Barrons in the film "Poltergeist" (1982) became her breakthrough role. Her portrayal of Tangina received praise from film critics and she went on to appear in the two sequels, "Poltergeist II: The Other Side" (1986) and "Poltergeist III" (1988).

She also appeared as a guest star in the television spin-off of the film, "Poltergeist: The Legacy" (1996), playing the clairvoyant Christina.

Zelda Rubinstein was known for her outspoken activism for little people and her early participation in the fight against HIV/AIDS. In 1984, she appeared in a series of advertisements promoting safer sex and AIDS awareness.

She also served as a spokesperson for "little people" and was an inspiration to many working in Hollywood. She was a regular on David E. Kelley's Emmy Award-winning television series "Picket Fences" for two seasons, playing the character Ginny Weedon.

Zelda Rubinstein appeared in numerous films and television shows, including "Sixteen Candles" (1984), "Teen Witch" (1989), "The Wild Card" (2004), and "Southland Tales" (2006). She also lent her voice to characters in the animated series "Hey Arnold!" and "The Flintstones".

Her last work was in the horror film "Behind the Mask: The Rise of Leslie Vernon" (2006). Zelda Rubinstein passed away on January 27, 2010, at the age of 76 due to complications from a heart attack.