Final answer:
The child must have a documented case of maltreatment to be eligible for the relative caregiver program, with the program's aim being to offer a safe space for children whose parents cannot care for them because of situations like maltreatment or incarceration.
Step-by-step explanation:
A crucial requirement for eligibility in the relative caregiver program is that the child has a documented case of maltreatment. This is in line with the information provided by the U.S. Department of Health and Human Services and the Administration on Children, Youth and Families, Children's Bureau regarding child welfare. The program is intended to provide a safe and nurturing environment for children who cannot be cared for by their biological or adoptive parents due to various reasons, including but not limited to, maltreatment, drug use, mental health issues, or incarceration of the parents. When a grandparent or other relative becomes the primary caregiver, it often links back to such conditions that make the biological parents incapable of fulfilling their parental duties.