Question: Who is the paternal grandmother of Nicholas Eliot, 9Th Earl Of St Germans?

Knowledge 1: Nicholas Eliot, 9th Earl of St Germans
Nicholas Richard Michael Eliot, 9th Earl of St Germans (26 January 1914, Marylebone, London – 11 March 1988), was a British peer.Eliot was the son of Montague Eliot, 8th Earl of St Germans and Helen Agnes née Post.He was educated at Eton and became a Captain in the Duke of Cornwall's Light Infantry, attached to the Royal Armoured Corps.He was a Justice of the Peace and DL.On 16 September 1960, he succeeded his father to become the 9th Earl of St Germans. [SEP] Knowledge 2: Montague Eliot, 8th Earl of St Germans
Montague Charles Eliot, 8th Earl of St Germans (13 May 1870 – 19 September 1960) was a British peer and courtier.Eliot was born in Pimlico, Middlesex to Charles George Cornwallis Eliot (16 October 1839 – 22 May 1901) and his wife Constance Rhiannon Guest (November 1844 – 1916).He was educated at Castleden Hall School, (Farnborough, Hampshire), Charterhouse and Exeter College, Oxford, taking a BA in 1893.By 1895, he was a Barrister-at-law at the Inner Temple.From 1901–1906, he was appointed a Gentleman Usher to Edward VII, and from 1908–1910 a Groom-in-Waiting.From 1910–1936, he was a Gentleman Usher to George V. During the First World War, Montague was a Lieutenant-Commander with the RNVR.He was appointed Officer of the Order of the British Empire (OBE) in 1919, and became Groom of the Robes from 1920–1936.In 1923, he was appointed Member of the Royal Victorian Order (MVO), and from 1924–1936 he became Extra Groom-in-Waiting toKing George V. He was appointed Commander of the Royal Victorian Order (CVO) in 1928; Knight Commander (KCVO) in 1934.In 1936 he became Extra Groom-in-Waiting to Edward VIII, and, from 1937 to 1952, Extra Groom-in-Waiting to George VI.From 1952–1960, he was Extra Groom-in-Waiting to Elizabeth II.He had been awarded the cross of Officer of the Order of Leopold (Belgium).On 22 November 1942 Eliot succeeded his older brother Granville Eliot, 7th Earl of St Germans to become the 8th Earl of St Germans.
Knowledge 1: Henry Eliot, 5th Earl of St Germans
Henry Cornwallis Eliot, 5th Earl of St Germans( 11 February 1835 – 24 September 1911) Henry Cornwallis Eliot was born in London on 11 February 1835 to Edward Granville Eliot, 3rd Earl of St Germans and his wife Jemima née Cornwallis( 24 December 1803 – 2 July 1856).Henry was educated at Eton College from 1845 to 1847, and served as a Midshipman in the Royal Navy in the Mediterranean Sea from 1848 to 1853.He was appointed as a Junior Clerk in the Foreign Office on 28 January 1855, where he worked until he succeeded to the Peerage in 1881.In July 1867, he was Secretary to a special mission of Earl Vane to St Petersburg to invest the Emperor of Russia with the Order of the Garter.He was an Assistant Clerk from 1872 until the death of his older brother William Gordon Cornwallis Eliot, 4th Earl of St Germans on 19 March 1881 when he succeeded as 5th Earl of St Germans.In the 1881 Census, he was living at 13 Grosvenor Gardens, St George Hanover Square, London [SEP] Knowledge 2: Peregrine Eliot, 10th Earl of St Germans
Peregrine Nicholas Eliot, 10th Earl of St Germans( 2 January 1941 – 15 July 2016), was a British peer and founder of the Elephant Fayre and Port Eliot Lit Fest.
Knowledge 1: Montague Eliot, 8th Earl of St Germans
Montague Charles Eliot, 8th Earl of St Germans (13 May 1870 – 19 September 1960) was a British peer and courtier.Eliot was born in Pimlico, Middlesex to Charles George Cornwallis Eliot (16 October 1839 – 22 May 1901) and his wife Constance Rhiannon Guest (November 1844 – 1916).He was educated at Castleden Hall School, (Farnborough, Hampshire), Charterhouse and Exeter College, Oxford, taking a BA in 1893.By 1895, he was a Barrister-at-law at the Inner Temple.From 1901–1906, he was appointed a Gentleman Usher to Edward VII, and from 1908–1910 a Groom-in-Waiting.From 1910–1936, he was a Gentleman Usher to George V. During the First World War, Montague was a Lieutenant-Commander with the RNVR.He was appointed Officer of the Order of the British Empire (OBE) in 1919, and became Groom of the Robes from 1920–1936.In 1923, he was appointed Member of the Royal Victorian Order (MVO), and from 1924–1936 he became Extra Groom-in-Waiting toKing George V. He was appointed Commander of the Royal Victorian Order (CVO) in 1928; Knight Commander (KCVO) in 1934.In 1936 he became Extra Groom-in-Waiting to Edward VIII, and, from 1937 to 1952, Extra Groom-in-Waiting to George VI.From 1952–1960, he was Extra Groom-in-Waiting to Elizabeth II.He had been awarded the cross of Officer of the Order of Leopold (Belgium).On 22 November 1942 Eliot succeeded his older brother Granville Eliot, 7th Earl of St Germans to become the 8th Earl of St Germans. [SEP] Knowledge 2: Henry Eliot, 5th Earl of St Germans
Henry Cornwallis Eliot, 5th Earl of St Germans( 11 February 1835 – 24 September 1911) Henry Cornwallis Eliot was born in London on 11 February 1835 to Edward Granville Eliot, 3rd Earl of St Germans and his wife Jemima née Cornwallis( 24 December 1803 – 2 July 1856).Henry was educated at Eton College from 1845 to 1847, and served as a Midshipman in the Royal Navy in the Mediterranean Sea from 1848 to 1853.He was appointed as a Junior Clerk in the Foreign Office on 28 January 1855, where he worked until he succeeded to the Peerage in 1881.In July 1867, he was Secretary to a special mission of Earl Vane to St Petersburg to invest the Emperor of Russia with the Order of the Garter.He was an Assistant Clerk from 1872 until the death of his older brother William Gordon Cornwallis Eliot, 4th Earl of St Germans on 19 March 1881 when he succeeded as 5th Earl of St Germans.In the 1881 Census, he was living at 13 Grosvenor Gardens, St George Hanover Square, London

Answer: Constance Rhiannon Guest