If I am looking at the right census entry for 1861 for John, he is showing as grandson to Duncan? Everyone born in Laggan
Duncan Mcdonald 55 Gamekeeper
Isabella Mcdonald 30 wife
Elizabeth Mcdonald 17 daughter
John Mcdonald 11 Son
Archibald Mcdonald 9 Son
John Mcdonald 6 Gamekeeper Grandson
Andrew Mcdonald 6 Gamekeeper Grandson
Address: Mealgarve, Laggan
You would need to look at the original image on
www.scotlandspeople.gov.uk to confirm the household entry.
Given the age of Isabella and eldest child in the house, a possible second marriage for Duncan?
Added: I think the age of Isabella is mistranscribed. There is a marriage for Duncan MacDonald and Isabel MacDonald showing in the Old Parish Registers on 18 Feb 1830 in Laggan.
Have you looked at the original marriage entry for John and wife Elizabeth Buchanan to see what details he gave for his parent/s? Possibility he might have been born illegitimately to a daughter of Duncan and also had a twin in Andrew.
From the index on Family Search there are two entries:
John McDonald born on 7 January 1855 in Laggan, Inverness-shire
Mother:Anne Mc Donald
Andrew McDonald born on 7 January 1855 in Laggan, Inverness-shire
Mother:Anne Mc Donald
These two entries would fit well with the household in 1861.
Monica