I have been looking for info on Catherine Pettigrew as well, she wouldhave been my 3rd great grandmother. I live in Canada, and what I know is that after Catherine died and Sampson (Samson perhaps) Arthurs (Birth 1799 in County Tyrone, Northern Ireland, Death 20 Oct 1858 in Argenteuil Quebec) came to Canada and he ended up living in Quebec with the 2 children,. The children were Robert and Eliza. Sampson married Anne Skelly (Birth 1810 in Balleymena, Antrim, Ireland, Death 27 Mar 1899 in Avoca, Argenteuil Quebec, Canada) and they had perhaps 8 or 9 more children. Eliza/Elizabeth married Arthur McCutcheon (Birth 1795 in Ireland, Death in Rivington, Quebec, Canada). I really know nothing else of Arthur other than I believe it is him in Newtonwards listed as "father" to a John Boyd (born 1929) when John married Mary Caughey (born 1831) in Newtownards in 1852.
Eliza and Arthur had 2 children,
Joseph McCutcheon (Birth 1856 in Argenteuil, Quebec, Canada, Death 23 October 1910 in Argenteuil Quebec, Canada
Catherine McCutcheon (Birth 1853, Argenteuil, Quebec I assume, Death 3 Dec 1886 in Long Rapids, Alpena, Michigan, USA). Little is known of her other than she married a Hugh McNeil son of Phillip in Montreal and moved to Michigan where she drowned in a well at age 33
Joseph (my great grandfather) on the other hand married Margaret Florence Young (Birth 24 Dec 1864 in Avoca, Quebec, Canada, Death 1952 in Rivington Quebec ) daughter of William Boyd Younng and Margaret MacLean. Joseph had 11 kids I think, and his son Russell married Pauline/Apoline Thomas (dit Tranchemontgne) and in May of 1923he slipped off an icy bridge that he was helping to build an he fell into the Rouge River and drowned, no body was ever found. Pauline his young wife had his daugher Nellie (still alive and almost 94) age 2 at the time, and 4 months later (in Rivington) she delivered Russell, my father(still alive and 92 this coming September). Later of course Pauline went on to marry again and hae more children.
So that is all I know on my end and I'm not sure it will help you, but Catherine Pettigrew has quite a few ancestors descending down from her on the family tree, alive and well, and I am just one of them- Sylvia McCutcheon