Her father was the writer and producer Alan Rinehart, son of the mystery writer Mary Roberts Rinehart. Her mother was Gratia Buell Houghton Rinehart, daughter of Arthur Amory Houghton, co-owner of the Corning Glass Company, and niece of businessman, politician and diplomat Alanson B. Houghton.
In 1948 Rinehart graduated from the Graham-Eckes School, Palm Beach, Florida, and in December of that year she made her debut at the New York home of her uncle and aunt, Mr. and Mistress Arthur Amory Houghton, Junior. In 1949 she married Doctor Robert Jean Campbell III.
With Breit she adapted R. K. Narayan"s novel The Guide for Broadway. The Guide opened at the Hudson Theatre in 1968, but closed after just five performances. The play, writes Professor of Theatre Arts Thomas South. Hischak, "was too foreign for Broadway critics and playgoers".
In 1973 Rinehart married the conservationist Hilary Barratt-Brown.
Her poetry collection Against the Loss of Night: Poems was published in 1986.
