Yes. There is a distinct 'half' symbol to be seen on the census. And Grandma talked of a half related James, but we assumed it was her younger, half brother. But maybe not it seems now. I am going to trawl marriages in Birkenhead and area for a marriage that may be relevant. I am also going to look in Barrow in Furness, as that is where the family ended up, and it is possible that older family members could've been up there in the shipyards before them.
I keep saying how much I appreciate the information from you over there - but I do! Thank you.