Popsit,
The information on the 1810 marriage record sounds normal for the time. All that was required were the couples names, the date and their 2 witnesses. It was 1845 before additional information became standard.
You are correct that Mary’s house was rented. She was renting from the farmer David Hill (who in turn was renting from the D’Huart estate). She had a farm labourer’s cottage on the Hill farm. Typically single story, 2 rooms, thatched roof. She’d have had a few perches of land to grow vegetables on. Her rent may have been paid in cash or by an agreed number of days work on the farm each year (which the farmer may not have insisted upon, if she was elderly). I assume that when William left for Australia or New Zealand, he would have ensured that his mother was not going to be destitute. You say he was a farmer in Ballygroobany. So he will have had a lease to sell, perhaps to raise the fare to Australia. Perhaps he sold his lease to David Hill, and a condition was that his mother could stay there. Or perhaps William had a sister who married David Hill and so they were family, and could look after Mary. Something like that? Just speculation, but it’s the sort of thing that might have happened.
Regarding the 1853 marriage certificate, it wouldn’t necessarily say whether William Orr senior was alive or dead. In some places eg Scotland, they were meticulous in recording that information, but in Ireland they rarely recorded it. So it just contains his name and occupation, regardless of whether he was alive or dead.
Statutory death registration only started in Ireland in 1864, so assuming I am correct in saying that William Orr senior was dead before that you won’t find a death certificate. In any event Irish death certificates don’t normally record the deceased’s parents names. (They do occasionally for a child but that’s it). The Church of Ireland does keep burial records, but again they don’t contain parents’ names. And in this case the relevant records for Mullabrack for 1813 to 1874 were lost in the 1922 fire (along with the baptisms).
Your best hope is finding the death certificate for Mary Orr. I looked at the Valuation Revision records (on the PRONI website) and I can see that Mary had left that house in Ballygroobany by 1869 as her name is deleted and the property marked as vacant then. So perhaps she had died or perhaps moved away. I looked at the death records 1864 – 1885, registered in Armagh (which is where a death in Ballygroobany would be registered). There’s only 2 of women of the right age. The first died 14.11.1871 aged 82. You might want to look at that death certificate to see if it fits. You can view the original certificate on-line on the GRONI website, using the “search registrations” option:
https://geni.nidirect.gov.uk
You will need to open an account and buy some credits. It costs £2.50 (sterling) to a view a certificate.
The second died 14.8.1880 aged 82 at Tullynmallogue. Her death certificate is viewable on-line free on the irishgenealogy site. She was a farmer’s widow. However that’s some distance away from Ballygroobany, and there was a John Orr farming there at the time of Griffiths. She was probably married to him. So I think it’s a different family.
Orr is a reasonably common name in Armagh. There were 155 in the county in the 1901 census. Mostly Presbyterian or Church of Ireland. So they are probably mainly descended from Scots who settled there in the 1600s as part of the Plantation.