Final answer:
The nurse would advise all family members to wash their hands after using the bathroom to prevent the spread of hepatitis A.
Step-by-step explanation:
The nurse would reply, "All family members, including your child, need to wash their hands after using the bathroom." Hepatitis A is usually transmitted through the fecal-oral route, so it is important to practice good hand hygiene to prevent the spread of the virus. Washing hands with soap and water for at least 20 seconds can remove the virus from the hands and reduce the risk of transmission. It is also important to avoid sharing personal items and surfaces should be properly disinfected to prevent contamination.