Final answer:
The percentage of lone-parent families with children increased from 1981 to 2006, which can be attributed to changes in social norms and family structures.
Step-by-step explanation:
The percentage of lone-parent families with children increased from 1981 to 2006. In 1981, a lower percentage of children lived with a single parent, but by 2006, the percentage had risen. This change can be attributed to changes in social norms and family structures. There has been an increase in unmarried couples, same-sex couples, and single-parent households, as well as the number of expanded households where extended family members live together.