In my Clan birth Index I have a David born about 1907 to W. John McIlhagga and Jane. In my Clan Marriage Index I have a William John McIlhagga (born about 1880) marrying Jane Burgess Anderson on 3rd September 1902 in Elmwood Avenue Presbyterian Church, Belfast, and I therefore deduce with a fairly high probability that David is their son. Furthermore, returning to my Birth Index I have the birth of twins, William John and Mary Jane on 19th February 1879 to Eliza Ann McIlhagga of Slatt, Ballymena. There is also the birth of another boy, James, to an Eliza Ann McIlhagga of Ballymena on 13th May 1872. These births imply a birth year for Eliza Ann of between 1850 and 1855. Also in the Birth Index (which I have compiled from various sources) these is a birth of an Eliza Ann in about 1851 to a William McIlhagga of Tullygarley, which could be one and the same. I wonder why William John and Jane called their son David? Perhaps it was the name of William John's father, and hence David's paternal grandfather. However, the same and perhaps a stronger argument goes for the eldest son James!
Do I then have a David born about 1907 who later married? There is just one possibility, a David Reavey born between 1904 and 1908 who married Elizabeth Gordon in 1942 and had three children born in the 1940s. I am uncertain of this Jane's maiden name so cannot say for certain that David Reavey is the David staying with his grandparents in 1911. There is however some circumstantial evidence. This William John and Jane McIlhagga lived at 161 Ormeau Road, clearly a house either next to or opposite the Anderson's at 160. The Census records that there were four children born to this couple and that there were four alive, though only three were listed as present at 161, and of course we know that David aged 4 was 'over the road' at his grandparents.
However, the three listed were David M aged 7, William John aged 6 and Agnes aged 2. Clearly someone, maybe the enumerator, had made a mistake. David R was not there, so the eldest child, who was indeed aged 7, must have been there. His name was Samuel James. Now the Census gives Jane's age as 32, thus giving her a birth year of 1879, the same year as William John was born to Eliza Ann McIlhagga. But the age of William John at 161 Ormeau Road in 1911 is given as 48, giving a birth year of 1863, a considerable discrepancy! At the present I don't know how to solve this problem. The enumerator may have made another mistake. If anyone can throw any light, I'd be very grateful.