Sexual gestures

My grandson just started acting a little wierd. I have raised two sons and never He is 3 years old.
He tells me to take off my shirt and when i ask him why he says "because I love you"
He also rolls back and grabs his butt and says coolo coolo. he said the pee pee goes in the coolo. He then rolls on his side and does a hump like gesture. I asked him what he is doing and he says, he is moving. I just think this is odd. He has started doing this about a month ago. I am really concerned about this. The other grandmother is the one who babysits for him. The only other person he may be exposed to is a little boy one year older than him, that the other grandmother takes him to his house. I am not sure how to find out exactly where this is coming from or should I not be worried?

[RockRose]

I would be concerned.  Kids do all kinds of normal exploration and like to use bathroom talk at that age,  but this seems beyond that.    He certainly seems to be simulating anal sex.

I think you're right to investigate this further.

[AnnieBrooke]

He might be exposed to something or someone else, at the house of the little boy who is a year older.  

[kirsteng266]

I would take him straight to a child therapist - they are able to speak to the children in a way were they are able to tell details.

I would try and keep him away from unsafe situations or situations out of your control. He needs therapy, he is definately being exposed to anal sex..... please do not leave this.

[spuds23]

yes. I will.
The funny thing I do not understand is why is he displaying this behavior to me? Everytime he comes to my house he does not want to go back home. But I think that is because I do a lot with him, educational games, park, play outside...etc..
Does he not do these actions in front of the other grandmother? Or in front of my son and his wife?
I told my son. My son is livid.  My son is going to tell the other grandmother to stop brining hiim over there immediately.  I am so ready to quit my job and start taking care of him. This really concerns me. His body shows no signs that anything physical took place. He also is very playful not shut down. So right now I think we can stop the visit and hopefully all will be good,

[spuds23]

well, my grandson will not be able to go to his friends house anymore. the only other thing which is a high possibility is that he has been exposed to TV shows on HBO where no one seems to be paying attention. That too has been stopped. But one thing for sure all will be vigilant because I take this very serious. Thank you all for your input. We will be monitoring his behavior this next week and see what happens.