Was just preparing stuff in preparations for doing research for someone in Co. Monaghan. On the back of 1821 census abstracts I decided to pull this stuff from First Monaghan Pres. Church in 1821.
Apart from Monaghan Parish some people travelled from the following 4 PARISHES and townlands into Monaghan town to attend this church. I know one person who actually lived within a 100 yards of their local church in Donagh but yet they travelled into Monaghan town which was quite a reasonable distance in those days esp with 6 kids...(It would be far enough today with 6 kids!!).
So while someone may have lived E.G. in Donagh, it doesn't mean they attended church in that parish. So if you can't find someone who lived in a certain townland in their "expected" parish church they may have travelled elsewhere too, regardless of religion. Townlands and parishes are only good indicators of where to start looking but as the above list clearly shows they are just indicators! I don't have 2nd Monaghan Pres. Church (Ballyalbany) done yet but expect it would be quite similar. If you can't find yours where they should be then look elsewhere....it wasn't illegal to attend a different parish or church then or now.
I did research for someone else whose family lived in Co. Monaghan but they couldn't find them, they lived near Monaghan/Cavan border and actually attended church in Co. Cavan. The family couldn't find them because they only looked in Co. Monaghan for them.