Anita, I don't know the whole story in your case, but "-chen" (and possibly "-ken"?) is a diminuitive suffix in German, that is, "little" or "young". It has been used both as a given name suffix and as a surname suffix. Since you found Bergken associated with baptism records only, I would guess that the suffix might have been added in those cases as an affectionate reference to denote a "little Berg". That would explain dropping the suffix as the child became older. The "-and" is another name suffix, whose meaning is unclear to me. David Uhrick