Frances I too confuse myself!
All I know for sure is that Robert THOMAS Corkill was christened Patrick, 1859. Illeg. son of Elizabeth Lace, who died young, aged 30 (ish) in Marown July 1867.
I can follow Tom from 1871 Census, living with his grandmother, Elizabeth Gelling, and her son John Lace.
I can't find Tom in 1861 census.
His father, was John Corkill, mariner.
I have researched John Corkill, Peel. Son of John Corkill and wife Jane. He can be tracked, living with Jane Corkillt o 1871. John is 29, unmarried, at Kinsale fishing.
In 1881 he is living with his niece Christian Gorry aged 17, and her mother Henrietta Quayle, nee Corkill/ Gorry, and her second husband Samuel, plus all their Quayle children. John is not with them in 1891. However in 1901 Henrietta is living next door to John W H Corkill aged 59 (born 1841) and his wife Ann J Corkill. Having written all that, I have absolutely no evidence that this is the John Corkill I'm looking for.