I'm going to have to join the chorus here and agree that you must separate them, all of them. Whether it's one snake hitting on the other, aggression or he's senile, separation is the absolute best solution. Things don't remain constant forever so count your blessings that they got along for so long but that kinship seems to be over. Why allow your smaller snake to get harassed?

On a side note, I think it's beautiful that you have 15+ year old snakes. I have 3 myself and can't wait till they get older. Any chance you'll show us a pic of them and their enclosure?

Good luck..

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