A childhood belief about father christmas

I first learned that Santa didn't exist when I found piles of presents in my upstairs closet, already addressed "From Santa." I was so upset that I showed my little sister and I refused to tell my mom. A few days later, my mom finally told me the truth, but, as the oldest kid, I couldn't tell my sister or my two brothers. So, to fix what I did to my sister, I told her that Santa only had time to give one present to every kid in the world, but he told the parents everything else you wanted so you wouldn't get two of the same thing. She believed it for another 3 years.