Can't find any of those names at the right sort of date in my tree. The only family I have at that date has Martha, Thomas, Jane, Katharine and Charles, born from 1775 to 1783, the children of Thomas Hiscocks (b 1747) and Sarah.
When you say "same town", do you mean Frome? If so, must surely be cousins at least. Do you have candidate parents for your family?