Unknown child of Josephine Margaret (now) Fraser. This unknown child is thought to be the parent of three children as mentioned in the Will, of Josephine’s new husband, Victor Trevor Fraser, dated 4 May 1980, found on Archives New Zealand Collections found online in July 2025:
"...for such of my wifes grandchildren DAVID COCHRANE, PETER COCHRANE and STEVEN COCHRANE as shall be living..."

First given name, initial of second given name, from New Zealand Electoral Roll - Te Atatu Main Roll 1978, found in July 2025:
Cochrane, Colleen J, 57 Sylvan Crescent, Married
Cochrane, John F, 57 Sylvan Crescent, Sales Exec
Cochrane, Stephen George, 57 Sylvan Crescent, Sales Rep
Cochrane, David J, 57 Sylvan Crescent, Clerk

Second given name (is same as mother;'s first given name), date of death, Place of death in Auckland [Green Bay, Titirangi], estimated year of birth of "1930", from Obituary of Colleen Cochrane found online in July 2025:
Colleen COCHRANE Obituary
https://notices.nzherald.co.nz/nz/obituaries/nzher...obituary?id=42105101
COCHRANE, Colleen Josephine. Passed away peacefully on 12 February 2021, at Pinesong Retirement Village, after a short illness, in her 91st year. Cherished wife of the late Jack. Loved Mother and Mother-in-law of David and Janene, Stephen and Robert, Peter and Raewyn. Devoted Grandmother to Aaron, Hannah and Matt, Lisa and Kane, and Bradley. Precious Great Grandmother to Lucy, Emily, Alice, Nathan and Ray. A life fully lived with dignity and grace. Due to COVID restrictions a celebration of Colleens life will be held at a later date. PLEASE NOTE that the date and time for the service will be re-advertised.

From search using suspected maiden name of “West”, year and country of death, date of birth, from death search on New Zealand BDM website in July 2025:
2021/5334. Cochrane, Colleen Josephine. Date of birth: 3 July 1930

Full date of death of 12 February 2021 confirmed from further searching in July 2025 on BDM Search by incrementally changing the date range for the death.