Interfering mum in law - how to sort out?

Share your ideas about the practical side of caring.
Hi all,
Does anyone have any advice for us? We live 30 miles from hubby's mum and brother.
His brother has chronic schizophrenia with anxiety and depression. She keeps letting herself into his flat and going through his stuff, throwing stuff out and reading his mail when he is not in. She has a key. He has begged us to put another lock on his door so she can only go in when he is there. She promises regularly not to do it again but then says how is she supposed to go in if the lock is changed?!?! - then does it again a week later. She is totally deaf to reason and always has been. When he goes out he never knows what will be missing when he returns. (She has always done this to both her sons with the result that even after 40 years of marriage if my husband can't immediately find something I am accused of chucking it.)
The problem is that he is a danger to himself when he is at his worst. She uses this as a reason for unfettered access "in case he hurts himself". We said she could call us any time she is worried and we will drive/train into London with a spare key to check on him but my husband would never forgive himself (and nor would she forgive him) if the delay caused his death. There are no nearer family members to give a key to who can be trusted not to give in to her and let her have a copy. She is very persuasive. She has multiple copies of everyone's keys stashed in her flat " just in case".
Although we are not technically their carers we are the ones who get the distress calls, try to remonstrate wth her and try to calm him down.
I thought maybe the threat of a new lock if she does it again? Her last warning etc.
Any other ideas?
Change the locks, get a "key safe" and put a spare in there. Make sure the GP and emergency services or whoever know what the number is (related to the date of birth is a good idea). No more driving into London though. You are not a puppet on a string, which is the way they are treating you!
Thanks for the suggestion. This is going to sound terrible but my hubby has just pointed out that she is more than capable of calling a false alarm to get the number, getting into the flat, ferreting out his spare key and taking a copy. We would then have to replace the lock again.....
However, it set me thinking about adding a digital combination lock to the back door ( its a ground floor flat) - number code not divulged except in emergency and then changed afterwards. No key to be secretly copied.
Thanks for the prompt.
Hi Judy
Just like with a child, threatening something then not following it though is not effective discipline. All people learn is that you do not mean what you say.
Sorry if this sounds harsh but on here there have been many instances of carers afraid to follow through, so only threaten what you would actually do.
As it sounds like you will have care issues building up, best to start setting reasonable but strict limits now. You will need them later on.

Neither mum in law nor brother in law can be fully treated as responsible
adults so you and hubby have to start assuming that role in their place. Sad, but necessary.
Kr
MrsA
Another thought. What about looking into new internet door bells/ keys? These can be monitored/changed from distance.
Have a look at key safes. They have a four digit code, so just the same as a door entry really, but a lot cheaper (around £20). The authorities who know the number, eg. doctor, should never divulge what it is to anyone else.
My disabled mum was prone to having falls and needing the ambulance, I wasn't necessarily around. She had a pendant Lifeline round her neck, and could alert a call centre. They had the number, and would call out the ambulance if necessary.
Quite honestly, your MIL sounds an absolute nightmare, she is more than interfering. Does she have any diagnosed mental health problem of her own?
She has never been diagnosed with anything. We (only laymen) think she has had lifelong adhd as you cant hold a conversation with her for more than a couple of sentences before she moves on . She changes subject mid-sentence. She is obsessed with clearing out and throwing away what she sees as rubbish whether it is hers or not yet she constantly replaces things, often duplicating. She sees nothing odd in things being in her flat but not knowing where they came from. It sometimes seems as though the concept of permanancy of objects passed her by in childhood.
She was widowed when the boys were 5 and 8, fell out with the inlaws and moved from place to place, working day and evening jobs to support them until they were down to living in 2 rooms, asked for council help and my hubby was taken into care! His younger brother went to live with grandma (who is another horror story). 6 months later the council saw economic sense and housed them together. So she has had a hard life and given everything she had to bring them up. Both are educated to degree+ level and are good, kind men. Both are compulsive hoarders.
I dont know what she was like before all this. Maybe it all stems from her bereavement. Who knows?
In spite of her behaviour I cant help but have enormous respect for how she survived and what she has acheived.
She is now very slowly losing her marbles, forgetting things, hard of hearing but doesnt like her hearing aids, physically amazingly fit and strong.
So this is mil. Nutty as a fruitcake in some ways but at heart a good person who would do anything for you.
Thanks for listening. Its good to put it down.
Well, my hubby has changed the lock in his brother's front door without telling their mum. We have a spare key. That was over a week ago and she has not yet mentioned it. I suspect that is because it would reveal she is trying to get in again after all the promises not to. She has been phoning us to say she thinks he is ill because he didnt let her in the other day but he's fine on the phone to us and his friend has the other spare key so we are not worrying about him.
So the new lock has worked without upset so far.
Thankyou everyone for being here for me.
I will keep you posted if there are any repercussions just in case anyone else is in the same situation.
Yes, threats are of little use, and last warnings must be precisely that. It is necessary to make it clear exactly where boundaries lie - which you have done - good luck.

Make sure brother-in-law does not leave the key lying around when mother-in-law does get access!