Hesketh was born on 23 December 1934 in Hamilton, to Lilian May Harris and electrical engineer Eric Bruce Mackenzie.

[1] Through her children's activities, Hesketh became involved in time-keeping and judging for water polo and swimming, and in the Mother's Union (now the Association of Anglican Women) and Girl Guides.

[1] Hesketh attended the Wellington branch meetings of NCWNZ as the representative of the Association of Anglican Women.

[1] Hesketh said later that she was expected by her family to be at home, and would not have been president of NCWNZ without having earlier separated from her husband.

[6] In the 1996 Queen's Birthday Honours she was appointed a Companion of the New Zealand Order of Merit for services to the National Council of Women.