Final answer:
Alternative family arrangements arise when parents cannot care for their children, leading to situations where three million children live with guardians such as grandparents or other relatives in an extended family structure due to various causes.
Step-by-step explanation:
When parents or guardians are unable to care for their children, various alternative arrangements are considered to ensure the well-being of the child. In 2018, three million children lived with a guardian who was neither their biological nor adoptive parent.
Causes such as parental mental health issues, drug use, incarceration, and physical or sexual abuse contribute to these situations. Often, children end up living with grandparents or other relatives in what can be described as an extended family structure.
About half of these children live with grandparents, and 20 percent with other relatives. Foster parents and non-relatives account for the rest, with state or city child welfare departments sometimes involved in formalizing these arrangements. The increase in grandparents acting as primary caregivers is a notable trend in these extended family structures.