Is it normal for me and my girlfriend to play with my dolls?

My girlfriend and i have been going out for 2.5 years and we such a great time together. Even though i'm 19 i still have my barbies and stuffed animals in my room(i have had them since i was 4 and cant get rid of them), and my girlfriend and i play with them when she comes over to my house. We do other stuff too but we both enjoy playing with my dolls. It turns both of us on so after we play we usually have sex. IIN?