Name, date and place of birth and death, place of burial, photo of George Henry Bartlett and Margaret Jane McDowell, from Find a Grave website found in May 2025:
https://www.findagrave.com/memorial/163845139/margaret_jane-bartlett
Birth: 12 Jun 1853, Antrim, County Antrim, Northern Ireland
Death: 6 Jun 1941 (aged 87), Auckland, New Zealand
Burial: Waikaraka Cemetery, Ōnehunga, Auckland Council, Auckland, New Zealand
Plot: Area 2 Block O Lot No 7
Memorial ID: 163845139
Aged 86 years
Daughter of John McDowell and Margaret Russell

Also, name of children from Find a Grave website found in May 2025:
George Henry Bartlett married Margaret Jane McDowell in Onehunga on 17th June 1875
Children -
1876 - Francis Rose
1878 - Elizabeth Jane
1881 - William John George
1883 - Mabel Emma
1885 - Andrew Richard
1892 - Ada Florence
1893 - Ethel May

The ‘Find a Grave’ page includes more children detail:
Frances Rose Bartlett 1876 - 1956 married Mr Abraham
Elizabeth Jane Bartlett 1879 - 1906 married Mr Lennard
William John George Bartlett 1881 - 1956
Andrew Richard Bartlett 1885 - 1917
Gertrude Emma Bartlett 1887 - 1963 married Mr Prior
Ada Florence Bartlett 1892 - 1973 married Mr Kelsall
Ethel May Bartlett 1893 - 1910

Record of burial from an Auckland Council cemetery search in May 2025:
Record for Margaret Jane Bartlett (nee McDowell)
Date of birth: Unknown
Date of death: 6 June 1941
Age at death: 86 years
Gender: Female
Region: Central and Hauraki Gulf Islands
Cemetery name: Waikaraka Cemetery
Plot location: Waikaraka Cemetery, Area 2, Block O, Plot 007
Remains type: Body
Date of burial: 6 June 1941