Karen, I have now researched the William Nethercott who suffered with deafness. He appears with his parents in the 1851 census and there is a mark on the column to indicate deafness or blindness. From somewhere between then and the census of 1861 he seems to have been moved to the Dulverton Union Workhouse - his deafness is recorded on their census sheets. He was not with his parents in the 1861 census and by the 1871 census his father seems to have remarried, probably after Sarah had died. William remained unmarried and probably died in the workhouse. I am continuing to work on the non-conformist angle in case that throws up any leads. However, Ellen Neithercott was born around 1857 so she should in any case appear on the civil birth registers, but for some reason she doesn't. Thanks for your interest.