Are they from Sligo or just Ireland generally? There will be few records that early regardless. Few parish records go back that far due to wars, fires and poor storage/conservation.
Only 1 parish went back as far as 1762 all others 1803+
also very few death records from parish records.
The closest dated census substitute would be the Tithe's of the 1820-30's, these are available at the National Archives, in Dublin or Ancestry.com and sometimes donated records from the NA collection.
www.censusfinder.com United Kingdom+Ireland+County
www.igp-web.com + County
Samuel died in Ireland before 1828 - you might be able to find a gravestone inscription. Heritage Societies often
do cememtary records and put in Journals.
Sligo as well as most Irish counties belong to a not for profit Irish Heritage Foundation, however, recently have changed to not just buying a copy of the record but now charge to search. You should be able to get the children's
birth records depending on the parish, you can search by father's name and Luke was fairly unusual then. These records would give you mother's maiden name. A good guess would be a marriage for Luke about 1804 and children following soon after. I would look for Samuel before the others as they are more common.
Griffith Valuation of 1858 Sligo show 36 Scott's occupying land, no one passing on the name Luke,Samuel or Matthew but
Robert and John's appear. Various Parish's.
www.askaboutireland.ieStill 97 Scott's in Sligo (includes some first names)so actually number nearer 20. Address's given are sufficient for mail delivery.
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