My cat, Pui Pui, is suffered from the bladder inflection and have crystal in the urine sample taken. It is the second time in seven months' time. Forgot to say, she is a 3 1/2 years old female Persian cat.

Same as Troy said, the vet said that she drinks too little water. Can anyone advise me how I can encourage her to drink more?

The vet also mentioned that one of the reasons may be because she is the only cat in the house and sleeps all day when both me and my husband go to work. I am now thinking to get one more cat. Do you think it's a good idea?

Does Apple Cider Vinegar help in this case?

AH, by the way, vets in Hong Kong only neuter kitten until they are at least 6 months old.