I too am researching a Westerhoff in Seward County, Nebraska. My great great grandmother, Minnie (or possibly Mildred) Elizabeth Westerhoff. I believe she married George Henry Alberti and had a son named Walter Carl Alberti.
Would you happen to know if your Jacob b 1828 or John Westerhoff b 1833 is related to Minnie (or Mildred) Elizabeth Westerhoff? I would think almost certainly they were.