My husband went in our 5 year old son room and was going to say good night to him and 10yrs daughter. When had went upstairs, he saw and heard with his own eyes and ears my 10yr old daughter telling my 5 year old son to get on top of her and my 5yr old son did not have his clothes on! My husband yelled for me as I ran upstairs he explained to me what he heard and saw... Both of childeren with nerves and didn't know what to say with tears in there eys! I asked what in hell is going on and they both couldn't answer me! I don't what to think of this my daughter said she wanted to know what it was and what would happen. I asked her so many times where she had seen this she made a comment that she had sen this with her older cousin that 16yrs old. But after asking her she changed her story. I don't what to do how to get help, do I call the police? I couldn't sleep all night crying the whole night as well. My husband and I don't how to handel this we are scared out of our life's. My daughter is the best behaved child respectful and always helps out! Now with this happening I don't what to do, I keep blaiming myself thinking maybe I did something wrong to have prevented this... I am so over baring with my kids I don't let speand the night with friends and bearly family thinking something like this may happen and now this in my own home! I don't know what to do, I scared for my 5 year ols son and scare for her as well

The first thing you need to do is find out what the 16 year old cousin has to do with your daughter's actions. There is a strong implication of inappropriate conduct there but you can't call the police until you have more information. It could be she saw something on TV while with the cousin... or it could be worse. Once you know where your daughter is seeing/learning this behavior, then you can figure out how to deal with the situation.

The daughter needs to be into a counselors office and see what has happened.
10 year old is when most start hearing and reading and seeing things all about the facts of life. By 12 some start even becoming sexually active now adays.

So have you have a very open and complete fact of lifes discussion with the 10 year old ? Or is she perhaps asking others she knows about it. ( which is how most find out) and from reading on the interent.

Do you regularlly check their internet history to see what web sites they are going to.
Do you know all of their pass codes to see what they post or do online ?

Before you go off in a panic, understand that it is not abnormal for your daughter to be curious. She is a little on the older side for this, but you said yourself that you are over bearing and they are sheltered.

I don't know if you could have done anything to prevent it since I don't know how well you have educated her about inappropriate touching and sex ed. It might be that you could have prevented it with more education. But there is no point in beating yourself up about, you can't change what happened so the question is how to deal with it.

And I agree with Chuck, that you should have them talk to a counselor. I have a feeling you may have scared them with your reaction and you need a professional to help you deal with it.

I agree, this may be all completely normal curiosity for the both of them.

And I fully agree with getting them into a counselor.