Sons name

So a few days ago we found out we were having a boy and since I already had a girl and boy name picked out since before we even conceived, I already knew we were naming him Bjorn Emrys. My husband all the sudden gets upset. Well I didn't get to name our daughter why can't I name our son. I told him before we knew the sec you were perfectly fine with the name I chose and our daughter is dead set on his name . I don't see the problem. Well now he wants our son to be named Knoxville. Can you guess why?! Yep from Jackass. A movie series I personally can't stand. I don't know what to do. Am I over reacting?