I want to write the first book from the MCs perspectives as children, and I picture it being a sort of a YA genre. A very wholesome but high stakes fantasy adventure. but I pictured the sequel as them grown up in their late teens and being more heavy handed on the romance, violence, and other heavy themes. I don’t want children tuning into book 2 and reading things that may not be appropriate for them. So, should I be targeting the first book towards teens/adults? Or really tone down on the adult themes of book 2? Harry Potter shifts through readership age really well, but that was subtly over the course of 7 books, not 2. So any advice would be appreciated!
Interesting dilemma. I’m sure someone more knowledgeable will come by with better advice, but my initial thoughts are that if you target YA for book one and have heavy adult themes later, criticism and impact on reputation is unlikely but worth considering. Personally I wouldn’t want to tone down my writing, but there’s nothing wrong with it. I think it depends on the YA age range likely to get their hands on your story. Knowing your target readers seems critical here. If book one is general YA with potential for children reading it, it seems like future books would be an different audience, which might not be great for readership. Even if the appropriateness level changes drastically, having the same well-defined target readership for both books seems the way to go to me. Is it possible for you to write book one the way you want to, but target the older subset of YA and avoid classifying or marketing it as a YA book? That might help cut out on the young readers but allow you to tell the story the way you want to.
I just checked, and Harry Potter isn't classified as young adult. Just because it's about kids doesn't mean it's YA. One thing you might consider is not having the books in the same series, even if they're about the same group of people. Don't give them a series title.
I have something similar I work on at times. The first few books are YA, in the way Lord of the Flies or Rumblefish is—the characters are 17 and have to start dealing with some pretty intense shit. A later book, not technically part of the same series but featuring the same characters, they're now middle-aged and we see how they've grown, in ways that could have almost been predicted from the personalities they revealed in the earlier books. But for one or two of them it's time to pay the piper for their earlier behavior, and it ain't gonna be pretty.
Every "MA" show on Netflix, Hulu, Amazon Prime solves this problem by loading up on explicit material in the first episode so that viewers will know what to expect.