A childhood belief about father christmas

I used to believe that my grandpa was the real Santa. Every year at my dad's company Christmas party he would dress up as Santa, and every year on Christmas Eve we would go look at Christmas lights and then when we returned home we would catch him in the house putting our toys out. He would walk out the sliding glass door and tell us he'd be back later, he had to deliver the rest of the toys to the other kids. He'd be gone for hours..