My 6 month old kitten bothers the two older cats, 7 & 8 years old, and they whine & hiss but don't fight back. This has been going on for 3-4 months. She will not change no matter what I do - squirt her with water, make loud noises, etc. Next step will be medication or new home. She has made our two oldest cats miserable and they don't even want to be in the house.