Just for information, it seems CIC changed Family size calculation compared to prior years, and it should be calculated for every year. For example if there are deceased persons, then they should be added to family size when they were alive, if there is divorce, then the ex spouse should be included in family size when they were married, for period from separation up to official divorce I couldn't understand yet. But there are same rules for marriage and child birth. When the person is married, the the family size should be more by 1 from the year of marriage.