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You don't mention the religious denomination but likely no records exist for anyone baptized in the 1830s in the Templecarn parish area regardless of religion. The Church of Ireland baptismal records start in 1844, RC records start in 1851 for baptisms https://registers.nli.ie/parishes/0290 and Presbyterian baptismal records are not available.
I also looked at the 1857 Griffiths Valuation head of household listing for Temple carn civil parish and I did not see a record for John Know or Isaac Walter Thompson so possibly they were deceased? https://www.failteromhat.com/griffiths/donegal/templecarn.htm
I did not see any Tithe records on the National Archives site.