I don't know how much research you have done regarding your grandfather. As for Josefa, I recently looked at the Ellis Island immigration pages again and see that she possibly became a citizen in 1943. This can be confirmed by contacting the archives in Washington.
There is at least one picture of Maryanna and Josefa Fiedura with my grandfather and three of the six children. Stanley, the only son with Maryanna, died in a tank explosion during WWII and is buried in the tomb of the unknown soldier in Arlington. All the children except one have passed away within the last 10 years. I believe just one may still be living, but she would be in her 90's and living in a nursing care facility.
The Rzucidlo's including the children and grandchildren of Maryanna Fiedura and Karol get together once a year in August for a family reunion picnic.
Can you trace your grandfather through Ellis Island or any of the census data? I think it is important to establish that your grandfather is related to Maryanna and Josefa.
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