What should I do?

Question

So my 3 year old daughter started touching her privates and said that my step daughter (10) showed her how to do it. Then my 5 year old son pulled his privates out last night and said my step daughter told him to do that as well. What do I do in this situation? What do I say to my husband? Will he even believe me? What would y’all do?
Edit: So I talked to my kids privately before my husband gets home and they went into some details that I just don’t think I was prepared to hear. My daughter said my step daughter touched my sons privates when they were in the room at night time and even “sat” on his privates. My son didn’t really say much except “yeah she sat on my privates and touched my privates”. I agree with some of you that something must be going on with my stepdaughter because she’s just not to an age where she would know all of this. She also told my kids not to say anything because it was a secret. I’m going to talk to my husband and tell him we need to wait until we get her and I will talk to her about it and we will decide what is the best thing to do after that. I am NOT mad at my step daughter because she is more than likely a victim herself. I treat her like my own and will definitely do what any mom would do in this situation and that’s protect my baby. Thank you all for the support. ❤️

Answer

It could be that your step daughter figured out that masturbation feels good and doesn’t realize it’s wrong and is just exploring with her siblings and thinks showing them this is harmless. Kids her age often experiment with this kind of thing. I really hope that’s all it is. 
Another very serious possibility is that your step daughter has experienced or is still being sexually abused. Someone else said it sounds like your step daughter is abusing your kids- 10year olds usually haven’t started to develop sexual feelings towards others yet so I wouldn’t personally jump to she’s trying to sexually assault her step siblings. I’d be WAY more concerned that she’s trying to make what’s happening to her (probably at the hands of an adult) be more normal. 
I would leave all other adults out of the conversation until I’d spoken to the step daughter. Talk to her in private, and be kind and open with her. Don’t cause her, do not make her feel bad. Be an adult who’s she feels she can trust and protect her. Depending on what she says go from there. If it’s just that she’s sexually exploring for herself explain it’s not ok what she’s doing with her siblings, that touching herself is normal, but to be done in private only. Let her ask questions. If you feel like she might be a victim of abuse take her to a doctor (honestly I’d probably still do this to be sure because she may be too scared to open up). Get her professional help and hopefully the disgusting animal doing this to her gets put away for life. 
Bring her dad into it IF it’s an abuse case (and sorry to say this- but it could be your husband which is why I said speak to your step daughter first, it could be any seemingly harmless adult in her life even her mother) otherwise, I don’t see it as necessary to discuss it with other parents as long as it’s dealt with. I know I’d have been mortified if my dad knew about certain things my mum talked to me about growing up. 
As for your little ones I’d talk to them too. Discuss private parts being private, etc. This is a good time to reenforce that they should tell you if someone is touching them in private places. Again, don’t make them feel bad or like they’re in trouble. Just be firm, but open so that they feel like they can always talk to you.

Answer

Call their pediatrician & keep your SD away from them.  The dr needs to see them bc it sounds like SD is abusing them.

Answer

This is a red flag that your step daughter can be getting sexually abused. Take all of them to their pediatricians to get looked over, talk with your husband, and y’all both talked with your step daughter; do not fuss or yell at her or make her feel guilty. It sounds like she’s getting sexually abused and doesn’t understand what it is and is acting it out on or for other children

Answer

I would talk to him and pediatrician and have a talk about why that's not ok...I don't know if it was innocent or not but I'm not okay with children Even exploring their bodies at a young age

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