My sister is being over-powering to my mother by making decisions for her but not for her benefit such as my sister has recently approved for a solar system to be installed on my mother's house, my mother does not need this solar system & has told me that my sister didn't ask as such but basically made this decision on her own accord. This system cost $12k, my mother's power bill is around $100 per month & she pays them off so basically when it arrives it's already paid in full. This is just 1 example of what my sister is doing. My mother has full capacity but like all mothers doesn't want to take sides. My sister is refusing to show me any documents relating to any purchase or any document for that matter & I know that she is being influenced by other outside family members.