Kia Ora,
I have found some information, but it will need a lot of checking out.
Angus born 1822 Bracadale, Catherine born 18/4/1823 Bracadale, Mary born 3/12/1830 Bracadale.
Angus dies 3/4/1873 Canterbury, Mary dies Roslyn Dunedin 19/2/1886. There is a tree showing father Ewen died in Snizort Inverness shire also 3/4/1873 so probably wrong date for Angus a mistype. However if this is true then Catherine would not have been a widow when she went to NZ. The tree also shows Ewen's wife Catherine dying in Snizort Inverness shire 28/1/1888 15 years after her husband died. two of her children had died by this point, so maybe she went back home to Scotland.
Regards.