Terry Holden's stepmother, Rosie, was diagnosed with amyotrophic lateral sclerosis (ALS), and Terry's wife, Susan, became Rosie's primary caregiver. Rosie executed a durable power of attorney appointing Susan as her agent. Susan opened a joint bank account with Rosie at Bank of America, depositing $9,643.62 of Rosie's funds. Susan used some of the money to pay for "household expenses to keep us going while we were taking care of her." Rosie died three months later. Terry's father, Charles, as executor of Rosie's estate, filed a petition in a Texas state court against Susan for an accounting. What general duty did Susan owe Rosie as her agent? What does an agent's duty of accounting require? Did Susan breach either of these duties? Explain.