Coit was born in Connecticut to Archa Willoughby Coit, a stockbroker, and Grace Coit (née Trow), the principal of a private day school.
At the start of the Great Depression, Coit's family moved to Greensboro, North Carolina, where Coit attended Curry School, a training school located on the grounds of Woman's College (now The University of North Carolina at Greensboro).