That is our family surname. It was not changed. Years ago a friend did some research and found a town in Poland called "Bielut". Which makes sense because people were always known by where they were from or what their vocation was.
Everyone I have ever known to bear this name in the US is family. They came in through
Ellis Island and were shipped down to Baltimore. Most settled into the east side of the city around Highlandtown and Dundalk.
Who is your friend, I wonder which branch of the family tree they are descended from..