I am not a Wilson descendant, but have been looking into my husband's cousin's lines.
His great-grandfather was George Wilson, born 11 Oct 1870 at Beglieve townland, Knockbride Parish, County Cavan. He and his brother Josiah (born 27 Dec 1873) were working as blacksmiths at Tullylorean, Canningstown, in the 1901 census. Haven't managed to trace Josiah after 1901, so he's a bit of a mystery. George married Margaret Wasson on 22 Dec 1914 in Knockbride Parish, they had seven children, and moved just over the border to Northern Ireland in 1926.
George and Josiah were among at least known chlldren of George Wilson (born c1828, died 20 Apr 1886) and Martha Marshall (born c1831, died 25 Nov 1900) who married at Aughnamullan, County Monaghan on 24 Jan 1854. Martha was from Monaghan, George from Cavan. Other children were Robert (DOB unknown) Elizabeth (18 Feb 1864) Mary Ann (13 May 1866) and Sarah (1 Sep 1868).
George Wilson (Snr)'s father was Robert Wilson who, I assume, was born around 1800.
My husband's cousin has visited the house,with adjoining forge, where his father was born in 1920 and has a photograph of it. This is also where George Wilson was blacksmithing in 1901.
I have also found another Wilson line in the same townland, who are almost certainly related, but I'm not yet sure how.
John Wilson (probably born c1800 - possibly a brother of the Robert Wilson mentioned above?) had a son called Robert Wilson (probably born c1830). This Robert married Elizabeth Wade at Knockbride Parish on 22 Dec 1864.
Their known children are:
George Wilson, born 26 Sep 2867, died 10 Mar 1947 in Philadelphia, USA *
Eliza Wilson, born 13 Sep 1867
Unnamed female Wilson, born 9 May 1870
Mary Jane Wilson, born 7 Oct 1871
Margaret Anne Wilson, born 8 Feb 1874
John Wilson, born 22 May 1875
Annie Wilson, born 28 Oct 1877
* George Wilson who went to USA married Catherine ? and their known children, born in Pennsylvania, are:
George, born c1896
Margaret, born c1898
Elizabeth, born c1899
Robert, born c1900, died c1901
John, born c1903
Anna, born c1905
If anyone reading this has any links to these Wilson lines, please let me know and maybe we can fill in some gaps.