Thanks for the response! I have very limited info on Thomas. I found a census record, but it puzzled me because Helga's name wasn't "Helga". But on another census I found, it was listed as Helga, but the last name was totally wrong.
I tried searching for the birthplace of Thomas, but I couldn't find anything because he was actually born in Norway. He and his family immigrated to the US date unknown. The birthplace is really important to me because there still might be relatives living over there. Thanks again for the response, and kinda clearing up the name-change thing.