mate, thats not normal, stop taking showers together
He is young so it s not such a big problem same thing happend to my son he was 11 years and his cusin (a girl) was 8 we were on holidays on island called hvar and they were staying a lot of times in there bedroom one s i wanted to go to the market and went inside the bedroom and i saw my son on the bed with nekad cusin under the bed giving him oral sex i completle lost it they were doing it for days i explaind that was wrong now is evrything ok he is 22 so i think its normal for kids trying this but i would still watch out
First, it is a good idea to separate them for bath time (or getting dressed, etc). Second, while this is obviously not ok- and it will be hard not to freak out about it- try to remain calm. Use this as an opportunity to being talking to your kids about their bodies, the purpose of their body parts, and why we keep them to ourselves. There may be more to why he did this, but it could also be simple curiosity.
To start, you will want to open the doors of communication- there are many resources out there that can help you approach conversations about body parts out there- one of my favorites is called "God Made All of Me: A Book to Help Children Protect Their Bodies- it is from a "Christian" perspective, so that may not be a good fit for your family, however, it has some really good information in it. You read it with your kids- it's a great tool. There are many other options out there, so if that's not a good fit, you can check out several others on Amazon or at your library. After you get the conversation going (not just about body changes, but a bigger conversation about what is appropriate and not)- you likely will be able to get a little more information on where the idea came from. Never be accusatory when you talk to him about this, this page has some good tips for how to start the conversation- https://www.rainn.org/articles/if-you-suspect-child-being-harmed
You will want to have similar discussions with your daughter, even at three (which you can start by using the same book- at her age she will catch different things, but start this conversation now).
Don't be afraid to reach out to your pediatrician for guidance as well, especially if you feel there is more going on than just what you saw.