Interested to read somebody mentioning the possibility of a "broomstick wedding" in this case - I've just read "Marriage Law for Genealogists" by Professor Rebecca Probert, who's the world's leading authority on the history of marriage laws and practices, which explains in detail that the idea of broomstick weddings (and in fact handfasting and all other kinds of 'informal' marriage practices) are complete myths - that's not to say that the grandmother hadn't heard of them, but that they were the inventions of Victorian folklorists and never in fact happened. I'd highly recommend her book if you want to get a much better idea of the different legal and social choices facing these people you're tracing.
