The Joseph Boons of Newport,Pagnell,Buckinghamshire,England

I am trying to trace my great grand father. I only have his first name,Joseph and that he married Jane Freeman.He remarried after Janes death. I know that three of his children, Arthur, Elizabeth and Henry, to Jane came to New Zealand.I would like to find out if there were any other members of the family, their names and any decendants they may have had.