William was born at Brechin, Angus, Scotland.
He married Janet (Jessie) Taylor (born at Perth, Scotland in 1806) at Coupar, Angus, Scotland in 1825.
They had eight children, all born at Coupar.
Jessie died in 1840. he then partnered with Margaret Reid (they never married - that we can find). She had one son, possibly with William as the father, as this son David John retained the Dalrymple surname.
They emigrated to NZ in 1853, landing at Port Chalmers. William purchased land at Waikouaiti where he was described, in the electoral rolls as a settler, freehold & gentleman.
One daughter, Learmouth, owned a town section in Levin from 1893 to 1906. She wa described, in the electoral rolls as a spinster, farmer.
Another daughter, Ann married a Peter Stewart in Foxton.