Yes, aparently they all (but one) have a middle name of Ford in honour of John Ford who died in a railway accident.
I checked the dates and the first child born to William Williams and Norah could not have been John Ford's so they were all William Williams-es
John Ford and Norah moved from Torrington, Devon to Cardiff and John Ford died a matter of months later. But William Williams appeared out of nowhere (I cannot establish, due to his common name) and only shows on the 1881 Welsh census.
I do have all the childrens birth certs but I just cannot find a marriage and you may well be right, they may never have married. He may have already been married
However with the find of a 'possible' father being a non-comformist, I thought I would give it a try but this guy (William Williams) is my brick wall so I did'nt expect it to be that easy

Thanks Carole