The couple had the following children, all born in Berwick -
- John James (1870, married Matilda Ann McCann in 1903 and died 1946)
- Amelia Jane (1872, married Justin Edward Sibert in 1890, died 1941 in Western Australia) It was Amelia's two sons, Frederick and Edward, who died in the War.
- Isaac Henry (1874 - 1875)
- Mary Anna (1876, married Francis Henry Montgomery Marsh in NZ in 1902, died 1962 in Queensland)
- George Peter (1878 - 1968, never married)
- Walter Israel (1880 - 1881)
- Joseph Arthur (1882, married Martha Elizabeth Glenn in 1908, died 1924)
- Albert Charles (1884, married Ruth Sherriff in 1909, died 1961)
- Clyde (born and died 1886)
- Alexander (born and died 1886)
- Ernest Edward (1887, married Daisy Campbell in 1925, died 1967)
- Emily Edith (1890 - 1970, never married)
- Clarence Eustace (1892, married Margaret Fogarty in 1918, died 1965)
Gardiner, George Peter (SN 4401) George enlisted on January 5, 1916. He was 37 years old, his occupation was Slaughterman and his address was Cockatoo Creek, a previous name for Cockatoo. George's next of kin was his father, James, and he Returned to Australia April 10, 1919.
Gardiner, Ernest Edward (SN 48) Ernest enlisted on August 22, 1914 at the age of 27. He was a farmer and he enlisted in New South Wales. He was reported as being 'dangerously ill' and invalided to Australia July 31, 1915 and medically discharged June 6, 1916. Ernest is incorrectly listed on the Embarkation Roll as Gardener.
Gardiner, Clarence Eustace (SN 4707) Clarence enlisted on August 7, 1915. He was a 23 year old fireman, working for the Victorian Railways. His father was his next of kin. Clarence was Wounded in Action - gun shot wound left ankle and compound fracture right thigh. Clarence was discharged on medical grounds on April 9, 1918.
Sadly, for James and Mary Gardiner, even though their four sons survived, two of their grandsons did not, Frederick and Edward, who were the sons of Amelia Gardiner and her husband, Justin Sibert, did not return.
Sibert, Frederick John (SN 3482) Frederick was born in Berwick and living in Blackbutt in Queensland when he enlisted at the age of 22 on October 18, 1916. He was a timber-getter. His next of kin was his mother, Amelia, of Yarloop in Western Australia. Frederick Died of Wounds received whilst fighting in France, on October 10, 1917.
Sibert, Edward Justin (SN 4551, listed in NAA as 4557) Edward was born in Collie in Western Australia and was 18 when he enlisted on March 1, 1916. His mother was his next of kin. Edward was Killed in Action, sometime between November 3 and November 6, 1916.
News has been received of the death of Private Sibert, an old Berwick school boy, and grandson of Mr and Mrs Jas. Gardiner. He was 18 years of age, enlisted from Western Australia, and sailed for the Front early last year. He was killed in France on 5th Nov. last when charging across " No Man's Land," when the Australians took Baupaume. He has a brother still in the fighting line, and also three uncles -Sergeant C. Gardiner, Sergeant major J. Gardiner and Private George Gardiner. Another uncle - Sergeant E. E. Gardiner who is now with us, took part in the memorable landing at Gallipolli and was severely wounded. Trooper Arthur Gardiner was at the South African war, where his brother, now sergeant-major, was twice mentioned in despatches by Lord Roberts. (Pakenham Gazette May 11, 1917)