You are correct about the neighbor babysitting for the family that rented from us. This young babysitter, who I likely knew because the family next door had like 5 girls, most old enough to sit in 1956/57, and they were still there when I came along in 1959. I think you're mistaken when you note she said it was their only child, it was stated she said he didn't match the unknown child. Common sense then should dictate this means there wasn't a "known" 4 to 6 year old boy there. When I was told this by investigators in 1999, I backed off my search and figured we couldn't help. About 2004, a local news story in Philadelphia had an investigator mention a forgotten fact about the child was that a long hair was found on him (his?), prompting this investigator gentleman to suggest he may have looked like a girl. Though this was thought to be possible in 57', it got little consideration. So at that point I couldn't help but wonder if it was possible that it was not known when the babysitter was talked to. Many feel this found child may have been slow, and he certainly was malnourished and mistreated. I thought that his dad, or caretaker may have been ashamed of his shortcomings and didn't want it to be known it was his son. He had the crude haircut that could be considered an effort to majorly change his appearance. Of course, if I could contact any old neighbors (I have tried), I would grill them to find out if they suspected any other children. The renters were quite mysterious, some neighbors evidently didn't know they had any kids. Also, this poor boy was buried in the bassinet box, could that have been because the renters had a baby and purchased the bed for him? I know a 2 1/2 year old should be too big for a bassinet.
I will say that a skeptic would think that there was enough evidence to figure we couldn't help (the authorities investigating, and the sister's words) but I am haunted by the fact my family moved back in to our house in March, 1957, just a couple of week's after this boy was found and the renters took off. One would think they would have chatted much with the neighbors. What was discussed, or discovered, if anything? I am told my mother more then once called the authorities - with no satisfactory resolution. Maybe she was wrong for this, I don't know the details, but if we lived there another 12 years (we moved away in 1969) after this happened, I am curious why my mother still felt it was mishandled. I would gladly accept it was handled correctly, I could then put my family's connection to rest. Sometimes I hear this case might be settled, and I am genuinely happy we may get his name. Then that comes to a dead end, and then I wonder if my parents, reasonable people who should have talked about this much with the neighbors, had reason not to forget about.