Mom fell over step into woman''s bathroom on tour boat, boat docked, not moving. Is boat owner liable for pain&suffering?

WA state, mom fell over step into bathroom. There are two tour boats which no steps are leading into bathroom except the ladies bathroom on one of the two tour boats. Fall happened two years ago. Mom never has been able to use arms since with raising them, holding something to read, bathroom or bathe self, nor dress or undress. She needs total care.Shattered both upper bones of arms. Surgery done on right arm only. Left arm had to heal on own. In Aug 2011 fell in home breaking right arm under metal plate and screws and broke left wrist. Family members placed her in nursing home to recover in which her bones healed but her mental state never returned to normal. Would like to know if the boat owner is liable for hospital bills and pain&suffering. This has affected her life. My dad and I are her caregivers at home. Thank you