Name from Birth search of son on New Zealand BDM website in June 2018:
1910/26451. Leo, Thomas William. Mother: Catherine. Father: Michael John

Other possible children from Birth search on New Zealand BDM website in June 2018:
1908/14199. Leo, Alfred John. Mother: Carrie. Father: Michael John
1911/10937. Leo, Clarence Michael. Mother: Carrie. Father: Michael

Do these NZ Electroral Rolls reflect our “Catherine”? Below she is spelt “Caroline” and not “Catherine”?

New Zealand Electoral Roll - Patea General Roll for 1928, found in June 2018:
Leo, Caroline, Brassey Street, Waverley, married
Leo, Michael John, Brassey Street, Waverley, linesman

New Zealand Electoral Roll - Patea General Roll for 1935, found in June 2018:
Leo, Caroline, Brassey Street, Waverley, married
Leo, Clarence Michael, Brassey St. Waverley, grocer’s assistant
Leo, Michael John, Brassey Street, Waverley, linesman

New Zealand Electoral Roll - Patea General Roll for 1938, found in June 2018:
Leo, Caroline, Brassey Street, Waverley, married
Leo, Clarence Michael, Brassey St. Waverley, grocer’s assist.
Leo, John Alfred, Brassey Street, Waverley, freezing worker
Leo, Michael John, Brassey Street, Waverley, linesman

New Zealand Electoral Roll - Patea General Roll for 1946, found in June 2018:
Leo, Caroline, Brassey Street, Waverley, married
Leo, John Alfred, Brassey Street, Waverley, freezing worker
Leo, Michael John, Brassey Street, Waverley, linesman

New Zealand Electoral Roll - Patea General Roll for 1954, found in June 2018:
Leo, Caroline, Brassey Street, Waverley, married
Leo, John Alfred, Brassey Street, Waverley, driver
Leo, Michael John, Brassey Street, Waverley, linesman

Is this record from Marriage search in June 2018 on New Zealand BDM website Our Michael and Catherine?:
1908/641. Bride: Caroline Setford. Groom: John Michael Leo

Maiden name of “Setford” (therefore matches above marriage record), date and place of birth and death found in June 2020 from:
https://www.geni.com/people/Caroline-Leo/6000000077136376194

Full date of marriage of 3 March 1908 from further searching in June 2020 on BDM Search by incrementally changing the date range for the marriage.