My grandfather just did a DNA test, and I have reason to believe that the last name of Sadecki may have originally been Sadowski. My grandfather's DNA shows him as having less than 1% Native American in his ethnic background (11 to 12 generations previous). This may be explained by John Anthony Sadowski, Indian trader and founder of Sandusky, Ohio. It may also explain why I cannot find any further Sadecki's in Pomerania before Adalbert. My grandfather got a 5th to 8th cousin DNA match on a direct descendant of John Anthony Sadowski.
That last name of Sadowski was changed to Sandusky by colonists in the 1700's. It may also have changed spelling from Sadowski to Sadecki in the following 100 years.
In addition to John Anthony Sadowski, there was also a Stanislaw Sadowski who arrived in Jamestown on the ship Mary and Margaret on October 1, 1608. He was said to be from the same family as John Anthony Sadowski.
If any other Sadecki's do the Ancestry DNA test, please inform me if you also show results of around 1% Native American and get matches on the last names of Sandusky or Sadowski. I think I may have found a missing puzzle piece in our family records.