Thinking some more about the surname 'Thirman', it could be Thierman or Thorman, or even Furman or Forman, if the clerk at the courthouse misheard the mother's maiden name.
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Michele Lock

Lock/Lak/Lok and Kalon in Zagare/Joniskis, Lithuania
Olitsky in Alytus, Suwalki, Poland/Lithuania
Gutman/Goodman in Czestochowa, Poland
Lavine in Trenton, New Jersey and Lida/Minsk gub., Belarus