Difference between sax and bass clarinet?!

So I have a friend that plays bass Clarinet but there's this kid in our band that keeps calling it a sax... we've tried telling him that they are completely different instruments. They don't even sound or look the same. He then proceeded to say that that the "black saxophone" didn't look like a clarinet.. Honestly they have barely any similarities.. saxes have palm keys and clarinets don't, saxes are made of brass, and clarinets out of wood instead of a octave key it has a register key, he still doesn't want to admit he's wrong but seriously... he's called a trumpet a trombone too.. idk if he's just fooling with us but he seriously looked confused when we told him that it's in the clarinet family 😭😭 is there any other differences?! I'm trying to not have him tell kids that the bass clarinet is a saxophone because we will have way to many if he does 😭