A 5-year-old boy is brought to the emergency room with a possible broken arm. His 18-year-old sister, who is also his primary caregiver, has come with him. The boy is relatively calm, but his sister is so upset she is nearly hysterical. The nurse notes that as her behaviors show more anxiety, the boy is getting more upset and his anxiety is also increasing. What initial action would be best for the nurse to take in this situation?