It is an intriguing matter to think about where this family might fit into the wider clan picture. The 'naming pattern' may not be helpful as the eldest son was named Andrew after his father rather than John after his grandfather. Perhaps John's father was Andrew? But if so I have no such record. It is of interest that no child was named after the paternal grandfather. The first daughter was normally named for the maternal grandmother which would be Lizzie's mother. The second daughter was named for the paternal grandmother which would make John's wife Agnes. But again I have no John - Agnes clan marriage. If Andrew was born about 1880 his father was probably born 1845-55. There were three or four Johns born in the 1840s but none seem to fit this family.
Now Andrew and Lizzie were married in 1906, just 5 years before the Census, and Andrew gave his address as Queen Street, not North Street, Ballymena. Presumably Queen Street was the family home, but the newly married couple moved into North Street. In 1911 we find John and Mary McIlhagga living at 115 Queen Street. Can there have been two clan families living in Queen Street? I think it is probably that John and Mary must have been related to Andrew and Lizzie. Andrew was 32 and John 30. John's father was also John, a Labourer, so surely they were brothers. Also John's witness at his marriage was a William McIlhagga. Was he another brother? Quite possibly. If we now go back to the 1901 Census we find a large McIlhagga family living at 67 Queen Street with whom I can see no link at present, though I would be surprised if there were none. There is also a 26 year old John McIlhagga at 102 Queen Street, married to a 25 year old Mary. Could they be the John and Mary of the 1911 Census who had falsified their ages to give the impression that they were old enough to marry? He was listed as a Carter, virtually the same occupation as 30 year old John gave in 1911, when he was a Railway Carter. The identification is born out by the Census 'Form A' completed in 1911. John and Mary declared that they had been married for 13 years and had had three children, none of whom had survived. John had therefore married at the age of seventeen and in 1901 would have been 20, not 26 as he declared.
There is a final 'clue' from the 1912 Covenant. The signature following that of Lizzie McIlhagga is that of a Maggie McCosh, as I have illustrated above. It is very probable that they would have been friends or even relations and as we have seen in earlier blogs, there is one McIlhagga family which married a McCosh family. William McIlhagga of Ballycloghan married Agnes McCosh of Clogh in about 1830. It is therefore possible that Lizzie and Maggie were (distant?) cousins. This is something we will have to keep in mind as we do further research, but for the present more than this we cannot say.