Hair can take a long time to grow back, often up to 6 months and sometimes longer if the skin has been traumatized. It is great her lesion has healed but I am concerned she is still digging at it. To me this says it could still be bothering her. I would talk to your veterinarian about further options; perhaps she needs a longer treatment. You were really inventive with the Velcro brace...my only concern would be the chance that she could get it caught on something and hurt herself. Unfortunately, I don't have better options to keep her away from that area. I don’t think it will be an easy option to keep something on her neck for the rest of her life. I personally would try to focus more on why she is still going after it and see if you can find something to keep her more comfortable or eliminate the problem completely.
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My cat Nikki is 10 years old. She had a "hot spot" on the back of her neck and after 
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