Thank you to Donald and Donna for your help. Yes, I have the 1881 Census information on the son Edward. But I didn't have Catherine's maiden name, date of marriage, or William's parents. For this I am most grateful.

It's a bit strange that on 1851 Census William's wife is shown as Catherine Christian, and yet the Christian part obviously didn't appear on the marriage documents. But now I know she's a CAIN so that gives me the right direction to head next.

Again, thank you.
Joan in Oz