He likes a 10 year old girl and he is 19?

Straight to the point: any 19 year old male that wants to have sex with a 10 year old girl needs professional help ASAP.  

have him go to consuling

This is a very serious matter.  Since he is admitting this to you, he may have already done something immoral or illegal and is reaching out for help.  Try to get him to talk to your local Mental Health Clinic or your doctor.  If he is unwilling, then seek counsel for yourself.  Do not take this lightly, thinking you can satisfy or change him.  Your child and yourself come first.  Do not marry this person unless this matter is completely cleared up.

There is definitely something wrong with this guy. And I have to agree with Barbaroni that since he admitted this, it's possible he's already done something inappropriate. I think your friend needs to give this guy an ultimatum: if he doesn't seek professional help immediately, she will leave him (and she has to follow through on this).

I ain't going to bet around the bush if any 19 year man say that he wants to have sex a 10 year old girl he "PROFESSIONAL" ASAP IMMEDIATELY!!!!!

There is no known cure for pedophilia.  Don't take my word for it, ask any expert.  Even when they wire them up and shock the you know what out of them when they look at images of children in various states of undress, they eventually get out of the facility or institution and harm another child.  That is basic behaviorial theory.  If that doesn't work, nothing does.  That would include so called counseling and seeking professional help which everyone seems to think is the be all and end all.  Anti-freeze will, though. 

Your boyfriend has serious issues. He is displaying pedophilliac tendencies which will only end in his going to prison for a very long time for "Rape of a child." This man needs to commit himself to a sexual treatment center where he can 1) get the professional help that he needs, and 2) where he is not a danger to society. It is believed that the man who abducted Somer Thompson of Florida suffered from the same predilection which hopefully he is caught and prosecuted to the fullest extent of the law. The same may happen to your boyfriend, is that what you want?