Hello,
I have looked at the Thomas Glass + Mary Jane McElroy pairing as I believe , but cannot prove , that Thomas was a younger brother of my Great Grandfather , Samuel Glass. Samuel Glass + Margaret Rae ( Wray) were married in Clogherney parish as were Thomas + Mary Jane, as you know.
This is such a small place, that it seems likely.
I believe Thomas + Mary Jane had these children that I can find so far :-
William James Glass b 29 Aug 1866 , Six Mile Cross, Co. Tyrone
Margaret Glass 14 July 1868 Co Tyrone
James Glass 28 Dec 1869 '
a possible marriage - Mary Anne Graham 16 - 11 1893 , Clogherney Parish
Samuel Glass 28 June 1871 Six Mile Cross "
John Glass 23 Mar 1874 Co Tyrone
These childrens names match the family names of the children of Samuel Glass + Margaret Rae.
Samuel Glass` father was Samuel and Mary Jane`s father was James McElrae.
Don`t know if any of that is helpful but it is what I have gleaned so far, Regards, Thommoje