If a sibling takes advantage of a demented parent's finances, will it affect their ability to get Medicaid in the future?

mom has dementia but can make decisions although poor ones. Decided to move in with brother who has taken advantage of large amounts of funds . I have tried to deal with it legally but cannot get myself bankrupt fighting for guardianship. How will she get care and Medicaid in future ? I know she will be needing 24/7 care in future that he will not provide when her funds are going down.