Interestingly my correspondent's information about no fewer than six siblings included three variations of our surname, McIlhaga, McIlhaggo and McIlhagga, and I have another to add myself. The key family which for my correspondent provides the progenitors, James McIlhaga and Rebecca Johnston, had these six children. When I compared the clan indexes I have compiled on births and marriages, and also the documents I have collected, I found that with a high level of probability I could take this family back a generation, albeit only to a man who was born about 1830.
I reckon that James' father was Nathaniel McIlhage who in about 1854 married Ellen. At this stage I do not know where Nathaniel was born, nor do I know Ellen's maiden surname. Below I will reveal how I know her first name. I was not surprised to find the name Nathaniel, partly because it appears in several other trees, and particularly because one of James' children was given the name. And I was not surprised to find a Nathaniel-Ellen marriage for one of the 'founding' marriages in another tree, that from Carnmoney, is of Nathan McIlhaggar to Ellen Wilson in 1830. Now another of James' children was named Wilson, which presumably comes from an ancestor's surname, so it may be that Ellen's Maiden Surname was also Wilson. I realise this would be a coincidence, though the fact that the two marriages are a generation apart makes me ask whether there might be a link that as yet I haven't found.
In 1872 Nathaniel senior was employed as a Gate-keeper, though I don't know where. He and Ellen had (at least) three children, James, Jane and Ellen. James must have married Rebecca Johnston in about 1877 and they had six children, Robert James McIlhaggo born in the Oct-Dec quarter of 1878, Wilson McIlhagga in 1880, Nathaniel McIlhaggo born 2 Feb 1883, baptised 24 February, Eleanor McIlhagga of 20 Liffey Street, Belfast, born 23 December 1885, Jane McIlhaga born 10 Jan 1889, baptised 9th February and Samuel McIlhagga born 7 June 1891 and baptised 27 June. Now Rebecca, daughter of Robert Johnston, a ship's carpenter, had a brother John who married James' sister Jane. So we have a brother and sister marrying a sister and brother, a McIlhagga-Johnston double linking. Rebecca was a witness at John and Jane's marriage while she was still Rebecca Johnston. John and Jane in fact married on 21st July 1873 at Eglinton Presbyterian Church, Jane being still a minor, giving her a birth year of about 1857. John was probably four or five years older. James McIlhage (the fourth spelling!) was John's witness. In 1873 John called himself a Spinning Master. I haven't yet researched whether John and Jane had any children, though one suspects that a reason for a minor getting married might well have been a pregnancy.
James McIlhaga is variously described as a Flax Dresser, A Hackler and a Rougher. Taking his children in order, Robert James at present I know nothing more about. Wilson appears in the 1901 Census, surname McIlhaggo, aged 20, boarding with David Jamison and family in Hillview Street, Belfast. As yet I haven't discovered a family relatiuonship. Wilson was a Sawyer in a factory. Next we come to Nathaniel, whose baptism at 41 Silvio Street, Belfast, gives us an occupation for his father. When Nathaniel was nineteen he joined the Army and from 2 June 1902 to 1 Jun 1908 he was serving with the Royal Irish Rifles, being discharged from what was clearly a six-year engagement, from the 3rd Batallion. In the 1901 Census Nathaniel was boarding with a Hinton family at 13 Fingall Street, Shankill, listed as 'nephew'. If we go back a generation we discover this is no euphamism. Nathaniel senior's other child was Ellen born about 1851. She was in fact the eldest, with James in the middle and Jane the youngest. Ellen married William John Hinton on 5 January 1872 also at Eglinton Presbyterian Church, hence making Nathaniel junior their nephew.
After discharge from 'The Rifles', in the 1911 Census we find Nathaniel junior having returned to live with the Hintons, now at 16 Linwood Street. Belfast. In 1911 he claimed to be Church of Ireland, unlike his siblings who were all Presbyterians and Congregationalists. Perhaps this was the influence of his time in the army. His 1901 Mill working had become 1911 Labouring. One of the documents I have in my possession is a Pension Application by Ellen in 1917 when she lived at 30 Rathlin Street, Crumlin Road, Belfast. Interestingly the application is made in her maiden name of McIlhaga, and on it she declares the name of her mother to be also Ellen, which is how I know that Nathaniel senior married an Ellen. In 1917 she was living in Mountpottinger Street, Ballymacarrett, Belfast. (The Pension Application also gives her married name of Hinton). Her husband, William John was, like James, a Flax Dresser. They had six children, Sarah, Ellen, Archiebald, William, Lizzie and Rebecca.
I have noted that Wilson lodged with the Jamisons. Interestingly in 1912, as revealed by the Ulster Covenant, David Jamison and his wife Sarah were living at 33 Linwood Street, Belfast, and next door at 31 there was Jane Robinson (nee McIlhaga), though there is no mention of Thomas Robinson in the Covenant. They must have been living almost opposite the Hintons and Nathaniel who were at number 16. Jane McIlhaga and Thomas Robinson married on 8 April 1908 at Clifton Park Congregational Church, and in the 1911 Census called themselves Congregationalists. In 1908 Thomas was, like his father James, a Coal Merchant at 6 Waterproof Street, Belfast, moving by 1911 to 20 Ballymena Street. Jane in 1908 gave the same address that her nephew Samuel had been born at 17 years before, 50 Rose Mount Street, Belfast. To the best of my knowledge Thomas and Jane had three children, Jane, Thomas and Nathaniel. My correspondent from this family is descended from Thomas. Most interestingly she has a brother who has been given the middle name of McIlhagga, thus perpetuating the clan link.
The last of James and Rebecca's children was Samuel born in 1891. At this stage I have no other information about him. A brief addendum to this story is the fact that in the 1901 Census there is a Rebecca McIlhagga boarding at Ambleside, Shankill. However this Rebecca is only 20, so was much too young to be the former Rebecca Johnston.