Though the age difference of 4 years meant something back then, it would mean something nowadays. It was only two friends who shared a nice friendship lasting only a couple years. There was nothing sexual involved;just two friends having some fun. Today, it may be looked upon as a crime. Then, it was just a couple kids enjoying each other’s companionship, that’s all there was to it.
I grew up in the 60s and seventies and we played similar games together just for fun. All we were doing was playing out everyday life as we knew it. Since spanking was a part of that every day life, we emulated it in our play.