Can my mother's trust funds, that were set up for her care, be used to remodel and create a bedroom in our home for her comfort?

My mother has a trust set up for her care. My brother is executor and will not share the information with my sister and I. He also is stingy with spending any on her care. She is suppose to be staying at each of our homes periodically but presently I have to travel over 400 miles for my turn to care for her which is a hardship. I would love to set up a room to accommodate her needs so she can stay at my home for a longer period of time. Is it reasonable to ask for funds to do this?If so, how do I accomplish this with my brother being secretive and tightfisted? Further, does my brother owe my sister and I explanation of how the fund is being handled? At present only he and his wife know and he becomes irate if the subject is broached. I appreciate any information.