I looked up Wakapuaka cemetery and found that both Isaac and George were buried in the same plot, along with George frank Harper aged 2 months, Dorothy Enid watts Harper aged 6 months and Mona Harper aged 1 day.
i went to the bdm index and looked up these children, there father was George Harper and mother was Florence Annie , George and Florence nee Dodson were married in 1888, they had 12 children the eldest born in 1889, and the youngest born in 1902. so going by the dates i say they would be Georges grandchildren.
Yes I found the notices of the children's burial too, (Harper family plot), guess they were Georges grand children although there is a couple of notices in the Nelson news papers about george Harpers wife Elizabeth, suing him for alimony in 6th Dec 1892. Also a School is also suing him for unpaid school fees for one of his children. May be a different George Harper??
I sent away to Elsie Curnow for a copy of the (W)Ratt family tree, pretty impressive book, heaps of stories, photos etc. and unfortunately she did not have much info on our generation of Harpers. $120.00 but am pleased with it.