By “two people making love to a child” I presume you are not describing an act of plural pederasty, but simply making an ambiguous choice of syntax.
You have crystallized my thoughts perfectly.
I mean showing nude consenting adults to a child. Either images or in person.
Showing nudity or natural lovemaking is a felony.
Yet showing violence and greed to children are completely allowed. In images, books and live shows.