@patricialamas firstly, why can't your portfolio (which I assume will be your website, as most are) have artwork geared for kids AND art geared for adults? It all has to do with how you organize it. Of course, if some of your adult work isn't appropriate for children, then it probably would be a good idea to split it up into two separate portfolios/websites/social media accounts.
I've seen quite a few professional illustrators, like Rebecca Green, that have a children's section and a editorial/licensing/"adult" section. They're usually organized under different tabs so it's easy to navigate.
As far as what's appealing to kids, think back to what you liked as a kid. If you create artwork that appeals to your inner child, what you would have liked to see as a kid, odds are that there are other kids out there that it would appeal to.
@Stephanie-H and @ArtMelC make a great points -- what type of art appeals depends on the kid and adult because tastes vary wildly.
When I look at your work on Instagram, there is a cohesiveness in your style even though some of the art is geared towards children and some towards adults. I'd love to see a portfolio on your website, even if it's only a few pieces. If you have enough pieces in both your children's and adult work, organize your portfolio into two categories. Then get a portfolio review from an art director, agent, or an experienced illustrator who also works in the adult and children's markets. And see where it goes from there...