Name, year and country of birth from search on New Zealand BDM website in October 2024:
1888/2298. Cox, Ivy Magdalene Vera. Mother: Charlotte Agnes. Father: John Duke

Full date of birth of 31 January 1888 from further searching in October 2024 on BDM Search by incrementally changing the date range for the birth.

Family photo added her in October 2024 on porch for family gathering at John (1856-1928) and Charlotte (nee Payne) Cox's house in Blenheim:
Back Row (L to R):
Seymour Arnold Cox (b. 1904)
Gordon Stanley Albert Rakena Cox (1902 - 1992)
Payne, Charlotte Agnes 1859-1924 married Cox
Queenie Elizabeth Cox (1888 - 1952)
Front Row (L to R):
John Duke Cox (1856 - 1928),
Ivy Magdalene Cox (1888 - 1975)
Brian Vincent Cox (1916 - 1976)
Vincent James George Cox (1882 - 1971)