I am also researching the Tkaczyk family of Gardner, Mass. However, I am focusing on Wladislaw Tkaczyk who married a Ptasnik around 1914. A cousin of theirs - and mine - was in their wedding and I have been trying to determine the relationship.
Is the Bronislas Tkaczik (as indexed in the 1910 census), your grandfather? It appears this Bronislas was the son of Adele, widowed.