Wivenhoe, I only have the three boys. I only mentioned Stornoway because someone attached, without explanation, the three boys to a Donald McLeod from Stornoway in FamilySearch.org. Unfortunately, the birth location for Donald snr is unclear.
I did look-up the Donald McLeod christened in 1823 in Cromarty but since he was a baker and moved to Rosskeen with his parents, is not likely a seaman and certainly is not the father of the three boys.
I am still unable to find anything further. Thanks for looking. I have written asking for the cause of death for Martha McLeod (nee Hossack), the place of death was Cromarty.