Fred -
The Robert Ziegler I found at Stanford looked to have middle initial of "H" and he was a Jr. Is this the same one you found? The H is for Hunt - middle name of the person born in 1935 and has residence in UT and CA and his DOB is 4-15-1935 which would have only made him 20 as of May 1955. I'm sure you've been on every page of the ancestry site - he wasn't on the census for 1940 as having been born in CA nor was he on the birth index. Hmmm. Does you cousin have her non ID info as well? Any mention of siblings for either birth parents? Any information about either of their parents (grandparents)? Is it known where they met (which state) ? Why Phyllis was in Illinois - was she sent there for her pregnancy? Any additional information - please let me know.
Kindest regards,
Michelle