Hi RobDev, I searched and found 5 James Devines or Devins born in the period 1797 to 1805, only two in Louth and others not nearby, only 1796 one in Laois about 100 miles from Dundalk. I asum you chose 1796 from the age at death which may not be totally accurate, 10 years out is not uncommon. The two in Louth were in Collon, about 20 miles from Dundalk, 11th July 1799, father James, Mother Catherine Boylan, sponsors John Hoy and Catherine Gargan, oddly I know a Gargan lady from Collon but she has no interest in genealogy. The other entry is for Ardee, nearest large town to Collon and 14 miles from Dundalk, in 1801, James Devin, no "e" father William and mother Caty Timins (probably Timmons nowadays) Owen Carroll and Ally Timins stood for the child. To be sure which if either are correct we would need the parents names known so we cannot be really sure either way and this is far back for Irish records, If you have the time you can check RC records here but difficult read. https://registers.nli.ie/parishes/0203 I have selected Collon parish.
Any reason she died in Newry and he in Dundalk, who was present at death, did he move in with a son or daughter, did you order the cert, cost €1 for copy of entry as for those years the free site does not show them, you can do it online here https://www.welfare.ie/en/Pages/GRO_Research.aspx only post 1864. Be sure to order coopy of extract rather than the €20 legal version.
By the way your selected name has political connotations here. A leader in the war of Independence was Eamon DeValera, who went on to a long political career, he was President and Prme Minister popularly known as Dev. The population may think Rob Dev is good or bad depending on allegiance but I doubt that was in your mind, gave me a smile anyway.