My brother is verbally abusing mom but she quickly forgets. Do we turn a blind eye?

Perhaps you could ask APS to do a visit. But think about what you are asking for.
If they want her moved, what will you do?
Is that what she wants? Will she remember him after he is out of sight? Does the verbal abuse seem to frighten her? Is it you that it bothers and not her?
Does he allow you to visit her alone?
Does he have DPOA for her? Does anyone?
Is she malnourished? Does she get medical attention? Is she clean? Are you coming in and doing all the work while he lives in her home?
What about your brother? Is he burned out or mentally unstable in other ways? Alcoholic? Does he need a break from caretaking? Could you take your mother for a few days for a visit?
Any change will require someone stepping up to take over the duties and will be upsetting to her. And a great deal of courage I suspect on your part. Do you have siblings or other family that will help you?
Why is the fact that the doors and windows are open upset you? Is the weather bad where she is? Is it noisy or dangerous for the doors and windows to be opened? Is he there with her all day?
As you can see, it's difficult to do more than say I'm sorry that you are dealing with this without more information. I know it is very stressful for all concerned.
Of course, it is always awful for anyone to be verbally or emotionally or physically abused and should be reported.
BUT you need to know what actions you are willing to take to pick up the pieces when the status quo is shattered.
If her dementia is advanced, she may adjust very easily to him being out of the picture or not. You do need a plan of action.
Let us know more. Come here to vent and perhaps someone can help you sort out the best course of action.

Even if mum is not "remembering" the yelling, etc, my best guess is that some part of her IS "getting it" and is hurt and frustrated by it. It IS most certainly abuse.

You leave so many unanswered ?? Maybe brother needs a break. Caregiving is very hard and many men (sorry to be sexist) simply aren't up to the task. If mum is 99, then brother could be---in his late 70's, easily. I can't imagine caring for my mother if I were 70, I can barely help her now and I am in my early 60's.

She deserves better care than taking herself to the bathroom and then being barred from sitting on most of the furniture. A dog would have a better life. In fact, a dog in the same situation would be forcibly taken away. Think about that?

Are the rest of the sibs scared of brother? This is not a 100% "his" problem, you need to talk as siblings and come to a better solution for mum. Don't come off angry, he'll just retreat and be defensive. Be kind, but have mum's best interests at heart.

If your mother was CHOOSING to sit on a kitchen chair all day (mine often does) that would be one thing. To be forced to do so, and forgo the comfortable seating available is cruel. Also, she could use some care as per her being cold all the time. Old people feel cold--esp on Wafarin--she's probably chilly all the time.

And WHY don't you want her going in a home? Her life now sounds pretty darn miserable. A home would be a blessing.

I am a caregiver with my father and I will not let anyone talk to him by cursing or getting short with them.
My father has a problem with incontinence and you just place a plastic on the chair/sofa and a towel and go on with life.
As a few have said turning a blind eye is being an accomplice.

This is abuse in any country, would you still be willing to turn a blind eye if it escalated to the physical side just because she forgets?
Unless your brother has always been a complete lout he sounds stressed to the breaking point, what kind of support are the rest of you giving? Can you not reason with your brother at all? Perhaps with a little cooperative brainstorming you can come up with solutions that help him feel less put upon and help her as well. Does she at least have a comfortable chair in the kitchen? If he is complaining of odour them perhaps a bath aide a couple of times a week? He says he wants to save his furniture, is she not using incontinence underwear? And they do sell pads to protect the furniture.

This is cruel and should not continue! She would be safer
and more comfortable in a home. It doesn't matter
that she forgets the poor treatment. Some people
are not good caregivers and your brother is one of
them.

Would you turn a "blind eye" if you heard this was happening to another adult? A child?
This is abuse.
It does not matter if she forgets or not.
Care giving is a very stressful thing to do.
I was given info once and I forget the actual % given but for my point it does not matter.
The report said 70% of caregivers admit that they have gotten angry at the person they are caring for.
My comment is that means that 30% of the people responding to the report lied.
EVERYONE gets angry. It is what is done with the anger.
Now what do you do.
Get someone else in to help care for Mom. That will relieve some of the stress.
The help could be daily or every other day. Anything will help. Schedule the care for when he needs it most. Are evenings particularly difficult? During the day? That is when you need the help.
You might want to think about placing her for respite for a week. This will surely give him a break.
And a full time placement might also be an option.
While you say she wants to stay home placement does have advantages. You can be a Daughter, a Son, to Mom again and not the caregiver. You will be more relaxed, you will enjoy visits more.

And I also think deep in her brain she does "get it", on some level she knows that he is yelling and is upset and she can not help but do what she does or doesn't do.
Try this...instead of yelling try to lower your voice and talk quietly, calmly while you are at eye level. I will bet that her posture will change and you will see her relax.

But it truly sounds like he needs help.
And again what he is doing is abuse.
My heart breaks for your Mom as well as you and your Brother.

Check out if there are daycare facilities for the elderly in your community. If so, Mom would be better placed there every day than sitting on a chair in the kitchen. It means u and your siblings would have to take turns in taking her. That way she would only be at home at night. Your brother would welcome the break each day.
Almost every town in USA have daycare and hopefully there is one not far from where u live. If u can't find one contact the local hospital and ask them.

Your brother is abusing your mother and a stop must be put to it. Sitting in a chair all day and is cold? Again, this is abuse. Sitting in a chair all day, being cold, verbally disrespected and abused is no way for anyone to live. Time to contact the proper authorities and have your mom placed in a reputable facility where she will be respected and cared for. A place where she can enjoy activities with others her age and make new friends.

As stated earlier, if your mom is 99, your brother must be in his 70's or at least late 60's. Caregiving takes a team of people. It is entirely too much for one person. I tried it for 10 months and nearly collapsed. I was doing everything myself - shopping, cleaning, cooking, washing my mom's clothes and keeping her area clean. She and a young family member in her very early 20's were sharing an apartment in which mom had her own bedroom and bathroom. My mom is 80.

I went there 6 days/week and hit the ground running with all the work that needed to be done PLUS take care of myself on the one day I had off! Took her grocery shopping one day and is where I almost collapsed. I then realized this could not continue.

Mom is now in assisted living in the memory care unit. What a God send. She has her own room and bath with a TV and small fridge for her bottled water, three chef-prepared meals per day and snacks. Her laundry and room cleaning are taken care of. She loves the staff and they love her even when she's throwing exploding F bombs. She is feisty at times and staff takes it all in stride. I go 1-2 times per week and take her out, shower her, lotion her down and clean clothes on if needed.

There's a garden area where she can go out and sit anytime she wants. The gates are locked so she can't escape and wander off. We go out there and sit, talk and laugh; call her friends and our family members back home.

I have my life back and went back to being her daughter instead of caregiver. She is happy, safe and secure having no worries about anything. My two sisters (who live in another state) and I have POA. I see to all her medical and personal things, paying the facility, etc and another sister takes care of all her financial things such as making sure all her bills back home are paid. We didn't get here easily as there is horror to this story. My sisters and I cut out the bad actors and the drama immediately ended. You may have heard about the horrors of family members close by who don't have time to help but want access to the money. Yes, that is a whole 'nother story. I could write a book.

All in all, your mom is being abused by your brother. She doesn't deserve it. Get the rest of your siblings together and put a stop to it now. Your mom should be able to live her remaining days relaxing in peace, comfort and quiet. Not sitting cold in a chair all day getting yelled at and being called disrespectful names.

"...go to the loo on her own." Are you by any chance in the UK?

No, anyway, you don't turn a blind eye. Not an option in any country, I'm afraid; only if you're in the UK I can be a bit more specific with suggestions. And 97 year old mom makes the excellent point that it's important to have at least a rough idea of what the alternatives are.

Hi, Yes I am in the UK and totally agree that perhaps we should leave well alone. Because the alternative doesn’t bear thinking of. Yes it does upset us that she’s on Warfrin to thin the blood and he makes her sit in the kitchen with the door and windows open all the time because he doesn’t want HIS sofa and HIS carpet having anything spilled on it i.e. Tea Coffee dinner etc. She no longer sits in the lounge where its warm and says she is cold BUT Im OK she says ??? He swears profusely at her calling her an idiot and other horrible words. But as we say seconds and its gone from her memory. Its us that it affects the most theres 5 of us he makes 6 His attitude is to keep us away as much as he can and its working.He says she only needs him.. Thanks for letting me let of steam. L. Bourne