I too am interested in discovering more info re: Cathcarts and name variants.
William Cathcart of unknown origin was listed on his son John's Marriage Certificate in Dublin 1848 as a Slater, but in later documents as a Gardener and a Farmer. On John's second marriage in 1853 at Preston, Lancashire he says his father William is deceased, but I have found no record of that yet. John says he was born in Ireland in 1828 and married Ann Bowles in Dublin in 1848, moved to Preston, where she and their firstborn ( William) died in 1850. He then married Jane Dickinson ( b 1832 Bolton-le-Sands - d.1875 @ Lancaster). Their children, James, George & Annie appear in the 1861 Census @ Kendal, Westmorland and in the 1871 Census ' Alloa, Clackmannanshire, Scotland and with the addition of another son (John b.1869 @ Alloa) and a daughter Jane , I think 1867,who died in infancy.
In the 1881 Census they are dispersed but John senior and juniorand Annie are all in Lancaster at different addresses and George is @ Kendal once again.
James is in the Royal Artillery and while posted to Isle of Wight marries in 1874 to local girl Ann Maria Mitchell. (d. 1885 IoW.)
Their 5th child is Alfred Edward ( sometimes William) Cathcart, b.1884 Freshwater, Isle of Wight who marries Gladys Emma Tubby of Norfolk at Northampton in 1925, and their 2nd child is my mother Gladys Ann Cathcart.
I have much information on cousins of most of them but a few mystery folks, such as George Wilson Cathcart b. 1875 Freshwater, Isle of Wight and the whereabouts of James Cathcart after 1881 Census at South Shoebury, Essex whilst still in the Army.
John Cathcart (b.1869 @ Alloa) marries Mary Dickinson and has a family when living at Chorley, Lancs ... 1891 & 1901 Censuses. I've yet to trace them after that.
Anything you turn up which helps me will be greatly appreciated.
If you check out the Cathcarts & Kithcarts of Panfield, Essex you will note a son named Walter and they had some family move to Durham before returning to Essex.