Thanks for the suggestions Sue and Frances. If I am reading the 1841 census correctly, the single line before after William (60) and before John (10) and Ann (20) means they are not directly related. Would a single line be placed before grand children?
We know from the 1851 census that the William next door is the son of the old William.
I have considered the possibility that Ann the mother of John had died, but have not found any good matches for deaths in the records. I guess it is also possible that both parents died or perhaps emigrated.
The theory that William married a second time is a possibility - but there is no sign of the second wife.
The 1841 census has a "Y" under place of birth for John, as it does for all other family members.
Thank you for the suggestions for the passenger list search Sue. I had the last two, but not the first two. Where did you find them?
Regards
Mary