This class contains information about a person related to the subject of the report (i.e., related to the patient). The ICH implementation guide limits this information to the parent of a child or fetus (usually the mother). However, this class is meant to handle other relevant related persons such as siblings of a child who had an adverse reaction to a vaccine. Note that each of the properties in the class exist in the Patient or Person classes. They are repeated here to emphasize that they are point-in-time observations that are needed for a particular report. Therefore, each of these properties are marked as derived - all of the properties can be calculated from the Patient and Person classes.