Hello!
I know it's a while since you posted this message, but I've only recently discovered my Cullen link. Margaret Cullen married George Lee around 1857. She is on the 1861, 1871 and 1881 census - I have this information if you would like it. She remarried in December 1882 in Berwick to either George Anderson or George Curry. I can't work out which. Isabella is on the 1861 census - but as Culley. I can't find her after that.
Hope this is of use.
Regards,
Carol