Can you make up your babies last name?

Does it have to be the mothers or fathers or can it just be made up?Can you make up your babies last name?
I believe you have to use the mother or the father unless there is religious reasons - some religions allow last names to be legal even though there is no heritage line attached.Can you make up your babies last name?
It depends on the state you are in, here in california as long as you say it's part of your family they dont care. You can say ';oh it's my great grandmothers last name'; and they'll let it slide.
As weird as it is....yes, you can make it up.





I don't know if this applies to all states....but where I am from it is legal! (I'm in NH in the US)
I don't think you can make up a last name for your baby.It has to be the Father's last name or the Mother's last name.
no stupid