Thank you so much for the information you gave me. Yes, unfortunately, my father's military records, along with millions of other American veterans' records between 1912 and 1973 were destroyed in a devastating fire in 1973 where military records were stored. All I could get was a certificate from the Dept. of Defense acknowledging that he was in the Army, his serial number and dates of service. I had his draft card so knew he was attached to the 3rd Army. Plus, he talked about it somewhat. The rest of the information I have had to research by looking at the activities of the U.S. 3rd Army ("Patton's Own") during WWII. When I saw they were the first American military unit to push into Czechoslovakia I was dumbfounded because I had known about his Czech mistress and the letter to my mother.
This is a very sad state of affairs for the children left behind, isn't it? I have a very good friend whose father was Polish and mother German, who became displaced after the war and only recently found his birth mother in Germany. While I don't know positively if my father had a Czech child, I wouldn't be surprised because of the fact he wrote to my mother saying he was in love with a Czech woman and wasn't coming home. Lucky for me, he did!
Thank you again. (P.S. my father's name was "Hatfield")