The proof needed came in the mail today! It was found on the Polish Genealogical Society of America website, where they have a database of the Chicago Polish Newspaper Obituaries. There were several in the Odron name . Andrzej Odron seemed the most promising. After sending $8, a SASE, and a request for Andrew Odron's obit, it was just one short week later a photocopy of the article arrived. It was in Polish, but isn't that what Google Translate is for? And the proof was there. As you can see below, it lists Marya and Waleria as his sisters. And lots of other great info!
From the Dziennik Chicagoski 1 Nov 1918
From the Official Chicagoski 1 Nov 1918
All relatives and friends of the most dearest and most beloved husband and daddy and our beloved brother, our late deceased,
member Polish Union of America and a member of Kosynierow Polish,
we inform you that after a short and severe illness,
he departed this vale of tears provided with the Holy Sacraments,
on 31 October, at 5 in the morning,
at the age of 30
The funeral will take place on Saturday, 2nd of November, at 8 in the morning, the house of mourning pnr. 2538 So. Western Ave., The church of St. Casimir and stam tad on the Lord's Resurrection Cemetery.
On this sad rite invite all relatives and friends, in a hard sorrow sunk.
Sophia, wife, Edward, Alexander, and Jeanette, children, Marya and Valery, sister, JohnCichostepki and Anthony Kaluza, in-laws.