In a discussion on contrivances, the subject of sex education (really just anatomy education) the subject of drawings versus photos was discussed. In the Will McBride book, photos were used but given that these are actual children, using their bodies in an illustrative text might be stigmatic and ethically questionable. The most obvious solution is to use realistic (and accurate) drawings. That way, the particular personality of the child would not be identified as some real person even if there was a life model originally. The amusing bit is that with the English-speaking world’s discomfort with frank presentations of the naked body, many books have become overly cartoonish, offering little useful detail. Ladybird Books was cited to by a number of readers as a good exception. Your Body was published in 1967 and a blogger (The Serendipity Project) took the trouble to scan its contents.
Robert Ayton – from Your Body (1967)
Interestingly, one of the other images in that book shows a family at the beach and guess what? The little girl is wearing no top! Yet another can of worms that has been discussed on this site regarding the convention of topless girl children on public beaches.
This is a general observation on the sex education books for children, such as the Will McBride book, but also other, like Tanja+Fabian, already mentioned at the Pigtails in Paint website (https://pigtailsinpaint.org/2015/11/playing-doctor-herbert-rogge-et-al/). I guess that these two books and many others published on the subject in the 1960s and 1970s in Europe (also in my home country), were not thought of as being stigmatic or ethically questionable, just because the models remained anonymous. This question is more serious in the case of famous photographers, who often use their children as models, and their identity is publicly exposed. However, in sex education books the broad anonymity could be maintained and the same applies to the illustration of nude children in advertisements, postcards, etc. If only the models were raised in an environment in which the human body is regarded as good and wholesome, and not something to be ashamed of, it was not a problem for them to be recognized by the extended family, peers or teachers. But I presume the main reason for using drawing representations of human bodies were significant cultural differences between America and Europe.
If in the old days, depictions of real children was not seen as stigmatizing in Europe, I do not think it should be seen as stigmatizing here in the U.S.
Now when on the other hand it is actual child abuse, that is very different. There have been some horror stories recently about sites on the “dark web” which had contained scenes of sex crimes against children.