Lord Dufferin took the name Hamilton by royal licence 9 September 1862, shortly before his marriage to Hariot Georgina Rowan-Hamilton on 23 October 1862.
He was distantly related to the Hamilton family by previous marriages, and the union was partly designed to eliminate some long-standing hostilities between the families.
Dufferin also took the name of Temple, on 13 November 1872.
They had seven children; the two youngest, a son and a daughter, were born in Canada:
Archibald James Leofric Temple Hamilton-Temple-Blackwood, Earl of Ava (28 July 1863 – 11 January 1900), was a lieutenant in the 17th Lancers and a fellow of the Royal Colonial Institute.
He was a war correspondent in South Africa during the Second Boer War and was wounded at Wagon Hill during the Siege of Ladysmith.
Lord Ava died a week later.
He was unmarried.

Lady Helen Hermione Hamilton-Temple-Blackwood (1865–9 April 1941), GBE (1918), LLD, JP for Fife, was married on 31 August 1889 to Ronald Munro Ferguson (later 1st and last Viscount Novar), who later became Governor-General of Australia.
They had no issue.

Terence Hamilton-Temple-Blackwood, 2nd Marquess of Dufferin and Ava (16 March 1866 – 7 February 1918)
Lady Hermione Catherine Helen Hamilton-Temple-Blackwood (1869–19 October 1960) trained as a nurse and qualified in 1901, serving in France during the First World War.
She was awarded the Médaille de la Reconnaissance française for her services.
She died unmarried.

Lord Ian Basil Gawaine Temple Hamilton-Temple-Blackwood (4 November 1870 – 3 July 1917) was a barrister-at-law.
He was at Balliol College, Oxford in 1891 and became part of the 'kindergarten' of Lord Milner.
He was appointed Deputy Judge Advocate in South Africa in 1900, secretary to the High Commissioner to South Africa in 1902, Assistant Colonial Secretary in the Orange River Colony in 1903, Colonial Secretary in Barbados from 1907 to 1909 and Assistant Secretary to the Land Development Commission of England from 1910 to 1914.
He was attached to the 9th Lancers and Intelligence Corps from 1914 to 1916 and then appointed Private Secretary to Ivor Churchill Guest, 1st Viscount Wimborne, the Lord Lieutenant of Ireland, in 1916.
He returned to active service as a lieutenant in the Grenadier Guards and was killed in action in 1917.
His most prominent legacy is the corpus of drawings he did for Hilaire Belloc's books (over the signature `BTB').
He was unmarried.

Lady Victoria Alexandrina Hamilton-Temple-Blackwood (1873–1938), whose chief sponsor at her christening was Queen Victoria, was married firstly in 1894 to William Lee Plunket, 5th Baron Plunket and had eight children by him, and secondly to Colonel Francis Powell Braithwaite CBE DSO.
Her son Terence Conyngham Plunket, 6th Baron Plunket was married to Dorothé Mabel Lewis, the illegitimate daughter of Charles Stewart Henry Vane-Tempest-Stewart, 7th Marquess of Londonderry, and both were killed in an aircraft accident in 1938, while her younger son Flight Lieutenant the Honourable Brinsley Sheridan Bushe Plunket was married in 1927 to Aileen Guinness, the sister of Maureen Guinness, who was later to marry Basil Hamilton-Temple-Blackwood, 4th Marquess of Dufferin and Ava.
Terence and Dorothé's eldest son Patrick Terence William Span Plunket, 7th Baron Plunket was an equerry to The Queen and Deputy Master of the Household, and their second son is Robin Rathmore Plunket, 8th Baron Plunket, the present baron.

Frederick Hamilton-Temple-Blackwood, 3rd Marquess of Dufferin and Ava (26 February 1875 – 21 July 1930)
Shortly after his marriage, he was deeply upset when his mother married his friend George Hay, Earl of Gifford, a man some 17 years her junior.
The marriage scandalised society, but Lord Gifford died only weeks afterward.
Despite his disapproval of his mother's second marriage, Lord Dufferin was devastated by her death in 1867, and built Helen's Tower, a memorial to her, on the estate at Clandeboye.
A nearby bay was also named Helen's Bay, and a railway station of that name was built there by him, seeding the growth of the modern Belfast
Lord Dufferin took the name Hamilton by royal licence 9 September 1862, shortly before his marriage to Hariot Georgina Rowan-Hamilton on 23 October 1862. He was distantly related to the Hamilton family by previous marriages, and the union was partly designed to eliminate some long-standing hostilities between the families. Dufferin also took the name of Temple, on 13 November 1872. They had seven children; the two youngest, a son and a daughter, were born in Canada:
Archibald James Leofric Temple Hamilton-Temple-Blackwood, Earl of Ava (28 July 1863 – 11 January 1900), was a lieutenant in the 17th Lancers and a fellow of the Royal Colonial Institute. He was a war correspondent in South Africa during the Second Boer War and was wounded at Wagon Hill during the Siege of Ladysmith. Lord Ava died a week later. He was unmarried.
Lady Helen Hermione Hamilton-Temple-Blackwood (1865–9 April 1941), GBE (1918), LLD, JP for Fife, was married on 31 August 1889 to Ronald Munro Ferguson (later 1st and last Viscount Novar), who later became Governor-General of Australia. They had no issue.
Terence Hamilton-Temple-Blackwood, 2nd Marquess of Dufferin and Ava (16 March 1866 – 7 February 1918)
Lady Hermione Catherine Helen Hamilton-Temple-Blackwood (1869–19 October 1960) trained as a nurse and qualified in 1901, serving in France during the First World War. She was awarded the Médaille de la Reconnaissance française for her services. She died unmarried.
Lord Ian Basil Gawaine Temple Hamilton-Temple-Blackwood (4 November 1870 – 3 July 1917) was a barrister-at-law. He was at Balliol College, Oxford in 1891 and became part of the 'kindergarten' of Lord Milner. He was appointed Deputy Judge Advocate in South Africa in 1900, secretary to the High Commissioner to South Africa in 1902, Assistant Colonial Secretary in the Orange River Colony in 1903, Colonial Secretary in Barbados from 1907 to 1909 and Assistant Secretary to the Land Development Commission of England from 1910 to 1914. He was attached to the 9th Lancers and Intelligence Corps from 1914 to 1916 and then appointed Private Secretary to Ivor Churchill Guest, 1st Viscount Wimborne, the Lord Lieutenant of Ireland, in 1916. He returned to active service as a lieutenant in the Grenadier Guards and was killed in action in 1917. His most prominent legacy is the corpus of drawings he did for Hilaire Belloc's books (over the signature `BTB'). He was unmarried.
Lady Victoria Alexandrina Hamilton-Temple-Blackwood (1873–1938), whose chief sponsor at her christening was Queen Victoria, was married firstly in 1894 to William Lee Plunket, 5th Baron Plunket and had eight children by him, and secondly to Colonel Francis Powell Braithwaite CBE DSO. Her son Terence Conyngham Plunket, 6th Baron Plunket was married to Dorothé Mabel Lewis, the illegitimate daughter of Charles Stewart Henry Vane-Tempest-Stewart, 7th Marquess of Londonderry, and both were killed in an aircraft accident in 1938, while her younger son Flight Lieutenant the Honourable Brinsley Sheridan Bushe Plunket was married in 1927 to Aileen Guinness, the sister of Maureen Guinness, who was later to marry Basil Hamilton-Temple-Blackwood, 4th Marquess of Dufferin and Ava. Terence and Dorothé's eldest son Patrick Terence William Span Plunket, 7th Baron Plunket was an equerry to The Queen and Deputy Master of the Household, and their second son is Robin Rathmore Plunket, 8th Baron Plunket, the present baron.
Frederick Hamilton-Temple-Blackwood, 3rd Marquess of Dufferin and Ava (26 February 1875 – 21 July 1930)
Shortly after his marriage, he was deeply upset when his mother married his friend George Hay, Earl of Gifford, a man some 17 years her junior. The marriage scandalised society, but Lord Gifford died only weeks afterward. Despite his disapproval of his mother's second marriage, Lord Dufferin was devastated by her death in 1867, and built Helen's Tower, a memorial to her, on the estate at Clandeboye. A nearby bay was also named Helen's Bay, and a railway station of that name was built there by him, seeding the growth of the modern Belfast
Frederick Hamilton-Temple-Blackwood, 1st Marquess of Dufferin and Ava