Something inspirational:
Extended family can be a source of happiness, but can also be a source of stress. It is okay to be at arm’s length to support them, but be in control of your own thoughts and focus on what you think is important. It is important to not let family interfere with your journey.
Family will always have opinions, but your opinions are what matter. We all have to fit comfortably into our life. When you're not doing it's because you're living another person's life, which means there may be an element of struggle.
I understand totally. But what if your family insist on involving you in their troubles, especially if it involves one of your immediate family members? Like my mother's issues with my daughter.
I know I should be the one to take care of her problems, but then again my mother won't let me be the mother. She never has.
I understand you totally. Letting your mother know and understand why you need to help your daughter will be the first step. The reason we don't say anything to our parents, is for fear of reprisal.
Your allegiance is to your own family and your mum has to know that. If the shoe were on the other foot, I am sure your mother will have wanted the same for her and her immediate family.