OK so here is what I have found from an account written by my father's cousin in a book called MacKenzie/McKenzie Tales.
Donald that came to New Zealand was born at Ullapool, Lochbroom 15 February 1825. His mother Abigail MacKenzie nee MacKenzie was born in 1788 and she married Donald (Donald's father) at Badluarach on 9 December 1812.
My father's second cousin suggests that Donald and Abigail's (Abby) children were Alexander, Margaret, Kenneth and William.
On an Ancestry record in the 1851 census there is an Abigail MacKenzie as I have mentioned before with an Margaret, Kinnith and William but they appear to be the children of a Janet McLeod? So I am maybe barking up the wrong tree.
But apparently Donald jnr left Scotland for the goldfields of Bendigo and Ballarat and went back to Scotland after getting enough gold and bought into a stock and grain partnership in Ullapool. However the business was not successful. This may have been around the time of his marriage on 15 February 1863 to Catherine MacKay in Tore, Killearnan. Donald Jnr went to New Zealand in 1867 on the Marco Polo and Catherine and the three children came over on the William Davie and arrived on 6 July 1870.
MacKenzie Tales does say that Donald joined his brother Alex in New Zealand.
Well I hope that one of you gene geniuses can connect my missing dots.
Thanks in advance.