I am a member of the John Adams line in question. I , too, was under the (incorrect) impression for a while in assuming the Adams/Napier marriage was a fact. There have been no records to my knowledge to verify this. There's a Dr. King of Anchorage AK who has posted and written much on this who will agree...unless something has surfaced in the last year or so.... The supposition isthat John Adams indeed was m. to a Katherine. For several generations thereafter, the name 'Nipper' Adams kept apearing in the family. That and the birth date/location of Katherine Napier led folks to thinking that the wife MUST be she.BTW....I've found over the years that people will putANYTHING in LDS records. I always look for decumentaion in any record to be able to verify it myself.
Is there a record of Katherine Napier's death? This would help eradicate the myth.