Trevor, You seem to be doing all the right things, so I'm not going to re-check you. I presume when you say LDS entries you mean user submissions. While not perfect, these are usually based on someone's findings, so shouldn't be completely dismissed. But I think your answer lies in census records, which you haven't mentioned. Being married in 1857, both William Checketts and Jane Clemens should be with their parents in 8141 and 1851 census. While 1841 will only show if born in or out of county, 1851 should show exact birth places. That should prove the link to George Checketts and Louisa Cook and give their origins. I'd then use the Hugh Wallis site to look at the batches for those parishes for earlier family BDM events. Peter