Hello Sheila, The book Bute & Arran Monumental Inscriptions pre 1855 has a Cumbrae MI for Robert Cunningham, died 18.7.1840, aged 62, and his wife Mary Hunter, died 30.9.1863, aged 77. Could this be your couple? They had a daughter Margaret died 30.8.1888 aged 69 according to the MI. Madeleine Wales *Bute & Arran Monumental Inscriptions pre 1855, edited by Alison Mitchell. Published by the Scottish Genealogy Society 1997