It's funny how when I did the OSU secondary last year, I didn't even consider that there would be overlap, but after reading the question over again, I feel differently.
Anyway, my personal statement was about ONE aspect of my desire to go into medicine. I attacked it from all angles. For the OSU question, I went way back to when I was young, and discussed all the developments in my life that led to my desire to be a doctor. Yes, I did mention the one big thing from the personal statement, but that was mostly a confirmation that I want to enter medicine, not a reason.
When I read over my secondary essays right before my interview, I thought they were really good, probably the best secondary answers of all my apps. I got in.
Good luck