I haven’t either, but I am like you. I always look at the pictures and keep my eyes open, just in case. So far, I haven’t run across any of them, but I do keep them in mind.
My problem is that a lot of kids (& adults) seem to look alike. But I’m always alert for situations that seem peculiar. Like a kid screaming too much. Could be just a temper tantrum. But on the other hand…
The screaming one is a tough cookie. I guess the best we can do is watch and if everything seems normal enough, maybe memorise a license plate number. The times I’ve tried to intervene have gone horribly wrong. Usually involving the suddenly-happy child grinning as it watches its parents berate me.
I have never seen one but… Many years ago I was visiting my in-laws. There was a knock at the door when I answered it there were two FBI agents standing there. I called my Mothrt-in-law over, she let them in and they started asking us about a little girl the neighbors had seen playing there.
It was my neice, she was living with my husbands parents at that time. The neighbors thought she looked like one of the kids that have their pictures on milk cartons and fliers that are mailed out here.
Thankfully the in-laws had all kinds of paper work including her birth certificate to prve who the child was and that they had the parents consent for her to be living with them. It was a freaky experiance.