code: private Person analyzeChild(final Person child, final Person prevChild) {
          Person retChild = prevChild;
          if (retChild == null) {
              return child;
          }
          final LocalDate birthDate = getNearBirthEventDate(child);
          if (birthDate == null) {
              return retChild;
          }
          final LocalDate prevDate = getNearBirthEventDate(prevChild);
          if (prevDate == null) {
              return child;
          }
          if (birthDate.isBefore(prevDate)) {
              final String message = String.format(CHILD_ORDER_FORMAT,
                      child.getName().getString(), birthDate,
                      prevChild.getName().getString(), prevDate);
              getResult().addMismatch(message);
          }
              retChild = child;
          return retChild;
      }
docs: Check the order of one child against the previous dated child.
  
  @param child the child
  @param prevChild the previous child
  @return the current child if dated