Do your kids need to know, that you shipped their cousin's box out? or can you hide theirs in a box, adressed to the cousin, and sneak away with sending the real one? For those with kids who still believe in santa, who leave milk and cookies, when I was younger my mom and dad took some white hair, or something and said that it was from Santa's beard... I know it's a bit off topic, but it strengthened my belief in him, as there was some evidence.