James Masterson : Short Biography

My Great Grandfather was James Masterson born circa 1867.  On the 1901 Census he stated his place of birth was "Ballybay" but I don't know any more than than, can't locate a birth record/baptism. I have summarised below what information I have.

James moved moved to Belfast were he Married Annie Toner at St Vincent de Paul RC Church in Ligoneil - North Belfast on 28/03/1880 (Belfast Urban 9 District)

James & Annie had 4 children

1. Thomas                01/03/1881 - Died at birth

2. James                  15/05/1883 - Mr Grandfather was married Agnes Hills

3. Maggie                 04/04/1885 - Married Hugh Mulholland

4. Annie                   22/03/1887 - Married William Burns

I have found death records for James 17/01/1907 and Annie 28/09/1918 (assuming these are correct).

On the Marriage Cert James Father is listed as Thomas Masterson a labourer who was still living at the time of their marriage.   I have tried searching various websites to locate Thomas in Monaghan but to no avail.  I did find a Thomas Masterson from Cavan - who married Jane Anne Carson 28/01/1859 in Cavan again, I think these are correct. 

My GG Grandfather Thomas also moved and lived in Belfast.  I found other Mastersons in the census records that I assume are Thomas and Anne's children, all I belive where born in either Monaghan or Cavan - to be verified, as Pre 1864 I can't locate their records.

1. Bridget            B: c1855 spinster  D: 11.07.1912 age 57 in Belfast       D: 11.07.1912 Belfast

2. Rose               B: c1857 had son Patrick Masterson unmarried ??       D: ????

3. Susan    -        B: c1863 - married Charles Graham                              D: 01.11.1921 Belfast

4. James   -        B: 15/09/1867 - Ballybay - married Annie Toner             D: 17.01.1907 Belfast        

I would really appreciate any assistance as I have hit a road block and would love to find out more.

Thanks in advance

Valerie