Grant was born on October 19, 1936 in Orlando, Oklahoma to parents Lawrence and Mae Thompson. She was raised in Wagoner, Oklahoma, and completed high school at Wagoner High School.

Grant enrolled at Northeastern State College (now known as Northeastern State University) in Tahlequah, Oklahoma, where she studied drama and speech. She became Northeastern State’s football queen in 1959. That year, she won the title of Northeastern Oklahoma Dairy Princess as well.

Grant appeared in local television commercials for Tulsa-based KTUL-TV after college. In 1962 she moved from Oklahoma to southern California to pursue an acting career. She initially worked as a teacher of special education and deaf students at Hollywood High School while trying to enter the entertainment industry.

She debuted on television in a 1963 episode of Bonanza. She soon became a contracted actor with 20th Century Fox. Her film roles under contract with Fox included The Pleasure Seekers in 1964, the 1966 science fiction film Fantastic Voyage, Our Man Flint in 1966, and The Witchmaker in 1969. Her television credits grew to include Batman (episodes 7 and 8), and Marcus Welby, M.D..

Grant married her husband, actor Chad Everett, in a ceremony held on May 22, 1966, in Tucson, Arizona. Chad Everett had been on location in Tucson filming the 1967 movie Return of the Gunfighter at the time of their wedding. They had two daughters, Kate and Shannon. Grant appeared in her husband’s television series Medical Center, in which he portrayed Dr. Joe Gannon from 1969 to 1976.

Grant died of a brain aneurysm in Westlake Village, California on June 25, 2011 at the age of 74. Everett died from lung cancer on July 24, 2012 at the age of 75, a little over a year after Grant’s death.