An 82-yeаr-оld wоmаn with mоderаte dementia is brought to the emergency department by her adult son for evaluation of a fall. On examination, the patient has bruising on the lateral aspect of the right arm, the posterior torso, and the left cheek. She appears fearful and avoids eye contact. When asked about the injuries, the son states she "fell out of bed," but the patient quietly says, "He pushed me." A review of the electronic health record reveals three ED visits in the past six months for similar injuries attributed to falls. The son insists on remaining in the room during the interview and frequently answers questions on the patient's behalf. Which of the following is the most appropriate next step in management?