Refers to the classification of census families into married couples (with or without children of either and/or both spouses), common-law couples (with or without children of either and/or both partners), and lone-parent families by sex of parent. A couple may be of opposite or same sex. A couple with children may be further classified as either an intact family or stepfamily, and stepfamilies may, in turn, be classified as simple or complex. Children in a census family include grandchildren living with their grandparent(s) but with no parents present.