I came up with part of your family in the 1891 census. Parents and 2 children are still there in Gairloch:
Donald Maclean head 74 Annabella Maclean wife 49 Isabella Maclean daur 25 Joanna Maclean daur 10
Daughter Annabella seems a bit young still to be married. For her age range (15-17) there is 1 Annabella Maclean in Edimburgh and 1 Annabella McLean in Resolis. If she appears in the census together with a Mary aged 18 that could help identify her. For Donald it's more complicated because there are more than 30 within his age range.
Isabella could be a good try for a marriage after 1891.
I'll let you know anything new I might come across with.