If your relatives are in a “new” area, your search for relatives in the area should include more than just neighbors with the same last name. Look at the first names, look at the places of birth for these neighbors. Does a neighboring family have children with many of the same first names as your ancestral family (hopefully ones that are not common)? Does that neighboring family have places of birth that suggest they could be related to yours or at least followed a similar migration path to the area where they are now living?
That’s a good way to find nearby families that are related to a family in a way other than through the father.
Sometimes it’s not the last name that’s the clue.