During their infestation of fleas, my oldest was always grooming. She groomed herself and her sister obsessively. After rounds of medication, and a few deep cleans, I’m pretty confident the problem is gone. I brushed them several times to make sure I didn’t find anything. My oldest looks great, full fur, clearly healthy. My younger kitty has not ever been a great groomer (hence why I assume her sister helps). Her poor tail is so thin, while everything else about her seems really healthy. I’ve had friends come over comment on her tail and I’m not sure why it won’t grow back. Does this qualify for another vet visit? I don’t want to spend more money if people think it’s a silly reason. They are about two years apart, I adopted them in 2017.