Hi Elaine, many thanks and I do appreciate about the privacy laws making finding more recent descendants difficult. I'll try searching among the family trees. I've looked at the passenger lists on Ancestry and found some of their movements but it was the younger members of the family that I was really looking for because that will then more or less complete my family tree. So far as I know there isn't a William Henstock in my family.
Thank you for helping me
All the best,