My kitty has overgrooming issues..

Hi vets, I was wondering if anyone would be able to help with this. I have been to about 6 vets locally where I am. They’ve done allergy tests, fungal tests, blood tests, food changes/trials, steroids and now she is on calming meds. She overgrooms to the point where her fur is gone. The vet said symmetrical alopecia as she does it same for the both sides. I have a 4 cat household, she was the first. Found her when she was 3 weeks. 4 days after, I brought in another kitten similar age. A year later, I brought in another. A year after this or more, she started the grooming (start of 2023) And about 3 months ago I had to take in another cat that had been dumped. Everyone is spayed. All female cats. The vet said to disregard the other cats as the timelines don’t match, she gets along with everyone and is really the sweetest baby, shows love her own way. Eats, poops, drinks water all normal. My vet has been searching for answers internationally and some suggest a cat behaviorist as it’s likely her mind that needs to be fixed. So currently, she’s on calming meds and I’m adding higher places for her and more hiding spots and boxes. Is there anything else we can do? I’ve also added a pic of her coat and pretty butt 3 years ago. Thank you in advance xx      

Hello - I think that it's a good suggestion to see a cat behaviourist.   Stress can manifest as overgrooming and, because cats did not evolve to cooperate in close proximity (by arguing or otherwise) bad feeling between them can manifest as stress, rather than the sort of conflict that is obvious to humans.   A lot of work has been done on toileting sites (for example, there should be one litter tray per cat and a spare and no cat should have to pass through another cats' 'terriory' to get to theirs).  So social stress may be one avenue for investigation. However, my understanding from the cat behaviourists is that a much overlooked cause of overgrooming in cats is actually underlying pain.  Cats can over-groom because of  eg arthritis, bladder disease or pancreatitis.  Because cats do not exhibit pain to their owners in the obvious way that some dogs seem to, this is frequently overlooked. Talking these possibilities through with your vet - or perhaps a veterinary behaviourist - sounds like a good next step.