Vivian Wilhelmina Myvett was born in British Honduras in 1881 to Francis and Margaret Myvett, a middle-class Creole couple. She attended the Anglican School and at 16 entered the pupil-teaching system, which allowed her to further her education in exchange for teaching. Graduating four years later with her teaching certification, Myvett taught for nine years in the Mayan village of Xcalak, Mexico. During this time, in 1905, she married Elizah Fitzgerald Seay. Having returned to Belize City around 1918, she founded the British Honduran chapter of the Black Cross Nurses (BCN) in 1920. BCN members visited homes and provided parenting training, instruction on sanitation, midwifery services, and performed general welfare work. In 1928, Seay and four other BCN members completed their formal midwife training at the Belize Hospital.

Seay led the BCN to assist victims of the 1931 Belize hurricane and organized a program to provide meals for school children. In 1933, after campaigning for a male Belize Town Board candidate, Seay was appointed as the first female member of the Board. She made numerous recommendations for the improvement of working women’s lives and was a supporter of divorce, as a countermeasure to adultery and illegitimacy. Legalization of divorce occurred in 1935 and that same year, she spoke against women’s suffrage, believing voting should be reserved for those who were educated. As a means of combating opposition to her stance, Seay proposed that unemployed women be granted land, houses, and training to learn to farm and provide for their families, but the plan was rejected by the Colonial Office.

In 1941, Seay became a public employee as Inspector of Midwives and then seven years later became the first female British Honduran Justice of the Peace. Throughout the 1940s, she supported the anti-nationalist goals of the administration and then in 1951, became the only woman founder of the National Party, which formed to contest severing ties with Britain. That same year, she accepted an appointment to the City Council when the governor dissolved the existing council. In 1952 Shea co-founded the British Honduras Federation of Women, which began a project to provide an inexpensive daycare center for the children of working women. She remained active in opposition politics throughout the 1960s. Seay died in 1971 and was posthumously honored with a street which bears her name and a postage stamp bearing her likeness.