Many thanks for that. I'll have to look at my research again. That all matches the 1841 Census except for the birth of Mary (but the 1841 census is notoriously unreliable for ages.) I found a George Batey there at Hanover Square, Newcastle. The parents were John Batey (b. 1791) and Elizabeth (b. 1801) both from Belford, Northumberland and married at All Saints, Newcastle in 1820 as I mentioned earlier, and that is not a match with Hannah Brown.
I'd like to believe the family rumours were true after all, and I already had found Hannah Dodds (the daughter of Ellen Boutland) but didn't know about the Boutland shipbuilding connection, so as you say, the circumstantial evidence persuasive.