I'm not sure if I mentioned this to you or not because I've told so many people about it. I have my 4 pee cats on Clomicalm, a medication that's usually prescribed for behavior problems in dogs but it's being used successfully on cats. It started working for me immediately w/no side effects whatsoever. I have them checked once a year just to be sure everything is A-OK. My RB Peeka peed on my hair one night while I was asleep. I actually heard it before I felt it run down my neck. Talk about urge to kill! She immediately scurried out of the bedroom and I had to totally strip the bed and take a shower at 2 AM. I was NOT happy. I didn't know about Clomicalm then or I would've certainly started her on it. That turned the tide for me as far as allowing my cats to sleep w/me. No more. Puddy does but that's because she's in CRF and has so many other health problems. But if she would ever do that to me, she'd be banished to her own room. Tell your MIL to talk to her vet about Clomicalm. Others have tried kitty Prozac and Feliway. I've not had success w/Feliway but others have so you may want to try that first but if you don't see results, Clomicalm has been a godsend to this household.