You can hold them responsible if they were at fault in causing his fall, such as, for example, if a staff member was trying to move him to change his bed and carelessly rolled him off the bed or lost his/her grip on him while helping him sit up, or if they were trying to help him practice standing or walking and didn't support him properly, or if, given his condition, he should have had bed rails or the like to make sure he didn't roll off the bed but they failed to have them. In any case where their negligence, or unreasonable or unprofessional carelessness, caused or contributed to his fall, they may be liable for injuries caused by the fall.But if they were not at fault, then they are not liable. So if, for example, there was no reasonable need for bed rails or restaints, and while your father was alone in the room, he tried to sit up or move on his own and that is why he fell, that is no the facility's fault and they are not liable.