First given name of “Ako” from obituary of daughter, Emma Louva Knauf found in June 2020:
“…Loved daughter of Ako and Jim Guttenbeil…”
Published in The New Zealand Herald on Apr. 5, 2018

From above obituary, Ako and Jim’s other children are “…Albert, Martha, Richard, Grace, Robert, Jack, Margaret, James, Nova and Etta…”
Published in The New Zealand Herald on Apr. 5, 2018

Given names combined of “Ako Christina”, year and country of death, date of birth, from death search on New Zealand BDM website in June 2020:
2013/30681. Guttenbeil, Ako Christina. Date of birth: 5 December 1920

Full date of death of 3 December 2013 from further searching in June 2020 on BDM Search by incrementally changing the date range for the death.

Full name of “Akosita Christina (Ako)” found in June 2020 from The University of Auckland Arts Facukty webpage for Germans in Tonga 1855-1960:
https://www.artsfaculty.auckland.ac.nz/special/germansintonga/?show=237
Surname: Sanft
First name(s): Akosita Christina (Ako)
Biography: Female, married Hermann Otto Richard Guttenbeil c. 1937. She was the mother of Richard Guttenbeil. (Despatch no. 76, date of despatch 24/04/1937; Richard Guttenbeil, Tonga).