Barnard Cothrell was born in the North End neighbourhood of the Corn Islands, a pair of islands off the coast of Nicaragua, to Halford Barnard and Caroline Cothrell. Her father was from the Cayman Islands, while her mother was a native to Corn Island. She was one of eight siblings, all pairs of twins.
Barnard Cothrell married and had five children, as well as several grandchildren, great-grandchildren and great-great-grandchildren. As a centenarian, she was affectionately known as “Miss Hazel” by locals. Her eyesight was sharp, and she could still sew. She also attended church every Sunday.
Barnard Cothrell died on 7 May 2022 at the age of 110 years, 94 days. She had been the oldest resident of the Corn Islands for many years, and only Mercedes Brenes Estrada and Celmira Somoza Sotelo de Espinoza were older in Nicaragua.
Barnard Cothrell was noted at the age of 103 in an article about the Corn Islands. Several Facebook posts were made celebrating her 110th birthday, and after her death.