Welcome! My name isXXXXX am a UC Davis graduate, and currently, a Medical Director of a veterinary hospital.
I am sorry to hear about this concern for Kara.
I have a Cavalier myself.
The medial patellar luxation problem is quite common.
Are you being cruel? No
There are countless pets that don't have the surgery performed. If it was a quality of life issue and clearly causing difficulties, than I would strongly encourage the procedure.
Now, will not doing the surgery cause other issues? Yes, over time, I would expect an accelerated rate of arthritis to develop in the knees.
So, not an emergency, but when possible, it would be nice if the knees could be corrected. Whether 3 months apart or 1 year apart doesn't matter.
But, no it would not be cruel. Medial Patellar Luxation
I hope that information has been helpful.
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