What Happened?

I was talking with my best friend Penny today over lunch. We were both talking about our weight loss journey. One thing that really hit me was the RAPID weight gain I had from 5th to 7th grade. The more I thought about it, the more it intrigued me. I am honestly considering calling my pediatrician's office to see if they still have my medical records (I am guessing NOT). Roughly guessing in my head, I gained about 75 pounds during that time. I just wonder what happened? My family had no emotionally traumatic events, etc. I know I can't turn back time, but I do wonder.