My great-aunt Mona Cattell married Guy Riblett in 1917. They had one daughter Marjorie (Margery) born Toronto 1924. She married Edward Jackson Smith in Fairmont 8 Jan 1944. Trying to trace any possible descendants is likely to be a nightmare (especially from overseas) as I have no idea where they settled. EJS's parents were Friend B Smith and Opal, but I've not found them so far on the 1940 census (while it is still free to search!). Any suggestions on how to filter-out all the wrong Smiths?