We avoid the green apples......the pairing of the two is obviously not the best idea.
We've lost 2 out of 3 we started with....and the 3rd, well, we affectionately call it "Hatchet Face" now. Let me show you why....

This is Hatchet Face when it was called GrannySmith.....

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And this is a few months later.........

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No, it isn't MBD, it is what happens to the Green Apples........not to mention the scoliosis and paralysis of some of the legs. We raised it to this point and I am a sucker and since it is not showing signs of pain, I will continue to keep it as a pet my little Hatchet Face.