Hello, June:
I had a similar finding. I believe the Parish clerk made an error when my
mother's grandfather named Robertson and his wife to be applied for
proclamation of the banns. He was listed as Robison on the parish record
together with the properly named girl. I found the two individuals with
names correct and an 8-month son with my grandfather's name in the next
census. I have yet to find a record that would change my thinking. In
the second following census I found Robertsons to support this conclusion.
I think the parish clerk just made a mistake. This may be your problem
also. Good hunting. Jim Dick, in the wet side of Washington State, USA
CALDERWOOD