I have a connection to Isabella Stevenson Gorman who married John Armour, 1845. She died 29.4.1874 in Milton Glasgow. Her daughter Isabella Stevenson Armour married Gregor Robertson October 1874 in Blythswood Glasgow.
Isabella Armour is listed on her death certificate as being the child of David Gorman and Isabella Gorman, maiden surname Stevenson. I am not sure if they are your Muirkirk family or not as there is another David Gorman who married an Isabella Stevenson in 1811 in Tradeston, Gorbals. They had a child, Isabella Gorman, christened Sept 1821. Have you any thing definite to tie Isabella Armour to the Muirkirk couple???