Thanks for sending us an email!
We are very sorry to hear about you losing your Jay minifigure but it sounds like your dad might have been right about leaving it at home. It sounds like you are very sad about it too.
Normally we would ask that you pay for a new one if you lose on of your minifigures and need to have it replaced. My bosses told me I could not send you one out for free because you lost it but, I decided that I would put a call into Sensei Wu to see if he could help me.
Luka, I told Sensei Wu that losing your Jay minifigure was purely an accident and that you would never ever ever let it happen ever again. he told me to tell you, "Luka your father seems like a very wise man. You must always protect your Ninjago minifigures like the dragons protect the Weapons of Spinjitzu!" Sensei Wu also told me it was ok if I sent you a new Jay and told me it would be okay if I included something extra for you because anyone that saves their Christmas money to buy the Ultrasonic Raider must be a really big Ninjago fan.