Hi, and thanks to all for your valuable input. Very much appreciated
Let me tell you what I have found on the past days since my previous message
a) I contacted National Archives of Ireland by email. They responded within 48hs and they response was something like "Morrison is not an Irish surname, most likely they were Scottish transplanted. Therefore they must have not been Catholic. 50% Church of Ireland records, the Irish version of Anglicanism, were destroyed in a huge fire in Belfast in 1922 and the parish of Lower Moville was affected, hard luck. However, we did manage to find an Abraham Morrison, child of John & Mary Ann".
b) I did my research on Abraham and got his death certificate from the GRO. He was an artilleryman at Woolwich Arsenal and died in 1905. A brother James is mentioned on his death certificate.
c) I searched on Geni, Family Search and Ancestry and came upon the package of information Bruce was kindly sharing.
So, where am I know?
John Morrison and Mary Ann Campbell were indeed married on 11 Aug 1846. I have found so far (on various sources) this issue (do you still call issue their children? my great grandpa used to employ that word):
John Morrison Jr (1850-1923)
George Morrison (1854-1915)
James Morrison (1856-1940)
THOMAS MORRISON (ca 1857/8- ca 1911)
Archibald Morrison (1859-1934)
Robert Alexander Morrison (1860-1924)
Abraham Morrison (1867-1905)
From all of them I have been able to find some piece of information, except from my direct ancestor Thomas, perhaps explained to that fire and him leaving quite young to Argentina. From family records he married in 1883 (at age 25 or so) and he stated as place of birth County Donegal only. Why did he leave is a mystery
John Morrison Sr 1817-1897 (son of John Morrison born in Scotland and Jane Tyler born in Inishowen, married around 1811)
Mary Ann Campbell ca. 1822-1896 (daughter of George Campbell and NN)
I am a bit lost with something. Within a county, for instance Donegal,are there any subdivisions? Because I see Lower Moville parish and Inishowen used indistinctively, is that correct? Then I see Greencastle and Carrickhue, these would be something like village and name of the house? I am lost.
Once again thanks for the feedback, cheers