I am a direct descendent of Mere Titope Kaikanui Pakanui of Ngai Tahu and William Harpur.
As far as Joseph and Sarah we have only been able to discover as much as has been posted here already. Sarah was also a convict I believe, although she may have been arrested in Ireland and they met up only in Australia. Joseph was arrested for trying to shoot someone and Sarah for stealing a handkerchief from a lady?? (sorry unsure as to the exact details). There are books on Charles Harpur published.
There is aparently a book published in New Zealand which talks a little about William and Pakanui, if this is any help.
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