Daughter does not understand her Mother (90) with dementia needs to be adjusted when sat for long periods. Advice?

Maybe you could give her an analogy of sitting in a car for a long drive. After a couple hours people can get a sore behind from sitting and stiff and need to stretch their legs. Also intermission at a theater or the seventh inning stretch for baseball. If she can recall when she got uncomfortable, it might make her more likely to agree. Plus maybe you could bring up the issue of potential blood clots from remaining in one position too long.

Maria, does not except that someone sat for a long time would suffer, as she as never sat long enough to experience discomfort herself.

What is Maria's objection to repositioning her mom they way you think she should?

Can you get mom's doc to tell her this? She may be inclined to believe the doctor more than you, her trusted friend, as hard as that is to hear.

The question was how to get the DAUGHTER to reposition her mother. Can you call the mother's doctor? Does a visiting nurse ever come by? Do you work for an agency? Any of those might have more "authority" in getting the message across.
Is the problem that she does not do it when you are not there? Is she a little too elderly herself to be able to do the repositioning? What is her reasoning for not doing it? Does the mother have any visible sores already?
You are in a bad position. You have the knowledge of what is needed. The daughter, like the rest of us, doesn't like to be told what to do. Also, she may think you don't know what you are talking about, although she is the ignorant one.
Can you tell us a little more about how you interact with the daughter?

They are Roho cushions.

Look for any pressure points. Heals are one place. Dad had blisters where the center tissue started to turn black. The problem was solved and he was given an air mattress. He was diabetic. I think they r called Rolo cusions for chair and wheelchair. They have gel in them and are adjusted for comfort by blowing them up. Expensive but the better.

There are special pressure relief cushions you can buy at a medical supply store. I bought one for my moms wheelchair and one for her recliner. You can find them online, too.

The suggestions above are spot on. Now how to get Maria to understand why it is important, pull up some pictures on line of bed sores or pressure sores. Once she sees how bad these can be she should hopefully understand. Thank you for showing so much love and concern for this dear lady. We need to speak for those who cannot speak for themselves.

Have you contacted Hospice? If they for some reason cannot help with home care though this sounds like something they could help with, they can point you in the right direction I would think. Are there programs in your area, senior services, that can help you address this?

When someone is on their bottom all the time they need to be repositioned every couple of hours. You are right to be concerned about this because repositioning sometimes falls through the cracks especially when there are other more important issues going on.

Every couple of hours take a pillow and slide/push it under the hip. Have the lady kind of roll to one side as much as possible to get that pillow wedged under there nice and firm. In about 2 hours move the pillow to the other side and repeat the steps in getting the pillow situated underneath her.

When the pillow is situated properly the lady should look as if she's leaning to one side a bit.

Getting Freda off her bottom will decrease her chances of getting pressure sores. You may also want to put a pillow between the knees while Freda is on her side.