Realize I am a couple of years behind with this one, but - my MAINS family were the ones that your George ALLEN married into. Did you by any chance come across any additional MAINS info in your research?
I have what you have already posted, the only commment I can make is that Fanny ALLEN as in 1891 census is actually Fanny (Frances) TATE on the original. She was Fanny MAINS, Mary Jane's dau from 1st marr.
Mary Jane was listed as a widow on her marr to George ALLEN, do you know any different? I THINK her 1st husband may have actually remarried rather than died!
Son Geo still in Middlesborough 1911.
You may already have all this info -just in case not!
Col