Name, year and country of marriage from Marriage search on New Zealand BDM website in June 2018:
1909/6539. Bride: Ella May McGregor. Groom: Thomas Song

Correction of surname to “Long” as per:
Birth search of daughter, Irene, on New Zealand BDM website in June 2018:
1914/14864. Long, Irene. Mother: Ella May. Father: Thomas

Confirmation of surname to “Long” as per: New Zealand Electoral Roll - Auckland East Supplementary Roll for 1919, found in June 2018:
Long, Thomas, 20 Stewart Street, Mt Eden, motor driver
Long, Ella May, 20 Stewart Street, Mt Eden, married

Full date of marriage of 1 April 1909 from further searching in May 2025 on BDM Search by incrementally changing the date range for the marriage.

New Zealand Electoral Roll - Manakau Main Roll 1949, found in May 2025:
Long, Thomas, Boyd Av., Mangere, retired.
Long, Ella May, Boyd Av., Mangere, married.
Long, Thomas Bevil, 17 Boyd Avenue, Mangere, butcher [Son]

Just Thomas and son (wife Ella died 1952) as per New Zealand Electoral Roll - Otahuhu General Roll 1954, found in May 2025:
Long, Thomas, 17 Boyd Ave., Mangere, driver.
Long, Thomas Bevil, 17 Boyd Ave., Mangere, butcher

New Zealand Electoral Roll - Manakau Main Roll 1957, found in May 2025:
Long, Thomas, 17 Boyd Ave., Mangere, retired.
Long, Thomas Bevil, 17 Boyd Ave., Mangere, butcher

New Zealand Electoral Roll - Manakau Main Roll 1963, found in May 2025:
Long, Thomas, 17 Boyd Avenue, Mangere, retired.
Long, Thomas Bevil, 17 Boyd Avenue, Mangere, butcher

Thomas’ son now married, living at separate address as per New Zealand Electoral Roll - Mangere Main Roll 1969, found in May 2025:
Long, Thomas, 17 Boyd Avenue, Mangere, retired.
Long, Thomas B. 78 Muir Rd. Mangere. Butcher
Long, Agnes M. 78 Muir Rd. Mangere. Married

Thomas no longer living with son at 78 Muir Road as per the New Zealand Electoral Roll - Mangere Main Roll 1972, found in May 2025.

Therefore, perhaps Thomas died between 1969 and 1972. Searching the New Zealand BDM website in May 2025, this was the only death - year and country of death, and estimated year of birth:
1970/46345. Long, Thomas. Died age 86Y [Therefore born circa 1884]

Full date of death of 18 July 1970 from further searching in May 2025 on BDM Search by incrementally changing the date range for the death.

This record found, which matches above, from Auckland Council cemetery search website in May 2025:
Name: Thomas Long
Date of birth: Unknown
Occupation: Labourer
Date of death: 18 July 1970
Age at death: 86 years [Therefore born circa 1884]
Gender: Male
Region: Central and Hauraki Gulf Islands
Cemetery name: Waikaraka Cemetery
Plot location: Waikaraka Cemetery, Area 1, Block D, Plot 103B
Remains type: Body
Date of burial: 21 July 1970
Funeral director: C H Barker Ltd