Slightly unrelated, but I wonder if a 17-year old child sends her dirty photo to a 18-year old guy she likes, who goes to jail? Just curious how the law works if there is no "abuse" element.
Both of them, still, in some places, although she may get more lenient treatment because she's a juvenile. Other places have cleaned that up in various ways, although I think he's usually still at risk unless he actively turns her in to the Authorities(TM) for sending the picture.
And there's a subset of crusaders (not all of them, admittedly) who will say, with a straight face, that there is abuse involved. To wit, she abused herself by creating and sending the image, and he abused her either by giving her the idea, or by looking at it.
Obviously, the laws were originally intended to protect children from malicious adults, but nowadays, when every child has a phone with a camera, they technically are one tap away from committing a crime even without realizing this. Maybe we should do surprise phone inspections at schools, or maybe we should restrict using camera app only to verified adults.
It comes down to prosecutorial discretion, and that can go either way.
Prosecutors have broad discretion to proceed with a matter based on whether there is a reasonable prospect of securing a conviction, whether it’s in the public interest to do so and various other factors. They don’t generally bring a lot of rigour to these considerations.
Obviously this depends on the country, but many countries have so-called "Romeo and Juliet" laws which carve out specific exclusions for situations along these lines.
I'm certainly no expert, but if my memory serves me correctly from cases that have hit the media, the carve outs are more broadly applicable than just to sex (e.g. intimate images between partners). But I could certainly be wrong!
(I didn't really want to start looking up the exact details of this topic while at work, so just went from memory. At the very least, the terminology "Romeo & Juliet Law" should give the original commenter enough to base a search on)