Brother grabbing ancestral property

Three-storeyed ancestral property, in father's name,father expired, no will left.

My mother and we three siblings are stakeholders .My brother has grabbed the entire ground floor (with pet dogs).My mother is staying at first floor. We all are senior citizens with health issues ( difficult) to climb up/ down to second floor,and we all prefer to stay at ground floor . How to resolve?

Thanks for your kind advice.

Regards