Thanks for that, Shane.
Unfortunately on the marriage cert we only have Wicklow, so maybe we'd have to start tracing father Bartholomew, hoping that that would give us a clue. He, or another Bartholomew was a supporter at Mary's baptism in 1894, but given Thomas age (from the 1911 census age given, he would be around 53 at this time), Bartholomew could well be in his 70s by 1901. Mind you, old John Sheridan was still living aged 75!
I have nagging concerns about whether we have the right Rose and Thomas... The number of children, Ann(i)e, her age when the last child is born...