I searched the Social Security Death Index for anyone with the surname Knapp who was born in 1935 (+/-5) and died in 1957 (+/-5), anywhere in the United States. Just two results: Larry and Norton. Both males. So, assuming the information about my maternal grandmother was accurate, she was probably not a Knapp--at least not when she died.
If you take the surname out of the search, you get 20,982 results. If you narrow +/-5 to +/-2, you get 3.633. Still a lot, but more manageable. And while the Social Security Death Index does not classify gender, you can infer most from the names. Unfortunately, though, many of the records do not have a last residence so further narrowing by state is not possible, even if we knew she lived in Pennsylvania (possible, but no real evidence to be sure). And then there's the not-so-obvious: If her name wasn't Knapp, how would I even know that I was looking at the correct result? I could very easily scroll right past the records I'm looking for without even knowing it.
Now, it gets interesting...
I also took another look at the Lehigh University Epitome yearbooks. Knowing that my birth father was listed as a 19-year old sophomore (presumably at the time I was born, in November 1975), this suggests he would graduate in 1978 (presuming he graduated on-time, and at all). Here is where it gets at least somewhat interesting. I looked at the 1978 Epitome for the most common names on my Y-DNA test results. The most common name was McHargue (with some variations as McCard). In fact, there is a 1978 Lehigh graduate with the surname McCard. He's still alive; and I found him on Facebook and LinkedIn. Still, the information I have is not exactly bullet-proof as I explained in my last post. Possible? Yes? Certain? No. It's not something that, without more, I'd feel comfortable going to him about. "Excuse me sir, did you happen to father a child while you were a student at Lehigh?" I'm not there yet. And--just to be clear--despite that you might feel as if you're helping--please do not take it upon yourself to reach out. If I get further information, I'd like to do it on my own terms.