Daisy mentions several times that it is inappropriate to hold Christmas in December, because Jesus has been born in March, as if it was a historical fact. There is, however, no religious or historical evidence pointing to this as the actual month of Christ's birth. It is unlikely that it happened in the winter, though, because the shepherds were out in the field. Based on when Zechariah fulfilled his duty as a priest and Mary's visit to Elisabeth, it can be estimated that Jesus was most likely born late September/early October.