Hello everyone. I have been following this thread with interest and have a few comments/ questions.
In the 1921 Canada census, I think Alfred's work might be Plasterer's Helper.
Have you looked at the image of the 1911 UK census with the Wilson household? I can't comment here due to RC rules but using what is available for free, there are only 3 Wilsons in the household: young Alfred Thomas age 3, Kathleen Josephine age 23, and Mary Alice age 68. They are living in Chorlton Lancashire, not Belfast as was mentioned in an earlier post.
Also, have you seen the original image of the passenger list with Kathleen and young Alfred? It appears to me that someone may have written widow for Kathleen. This is written over what would have originally been written, presumably by the person who conducted the immigration interview?
I think the absence of Alfred from the 1911 household and the possible designation of widow for Kathleen in the passenger list might lend some credence to the estrangement theory. If Alfred was already in Canada and she was coming to join him, it would normally indicate that she was going to join her husband, if I remember correctly.
I haven't been able to find Kathleen or young Alfred in the 1921 census either.
Anyway, a little food for thought.
PB