Grandparents’ disclosure that minor children had Indian heritage triggered a duty for the Agency to further inquire. The minors were removed due to mother’s drug and mental health issues, an unsanitary home, and domestic violence between the parents. At the detention hearing, both parents claimed they had no known Indian ancestry. Following an unsuccessful reunification period, the maternal grandparents sought placement. At a permanency hearing, maternal grandfather reported that the minors’ great-grandmother was an enrolled member of the Yaqui tribe. No further inquiry was conducted. Parental rights were terminated at the Welfare and Institutions Code section 366.26 hearing and the Indian Child Welfare Act (ICWA) was found not to apply. The appellate court reversed and remanded to comply with the inquiry and notice provisions of ICWA. ICWA defines an “Indian child” as a minor who is either “(a) a member of an Indian tribe or (b) is eligible for membership in an Indian tribe and is the biological child of a member of an Indian tribe.” In addition to the initial duty of inquiry if a minor is an “Indian child,” the Legislature has imposed a duty of further inquiry if information becomes available suggesting a child may have an affiliation with a tribe, even if the information is not strong enough to trigger the notice requirement. The required inquiry must include interviewing the parents and extended family members, contacting the Bureau of Indian Affairs and State Department of Social Services, and contacting the tribe or tribes and any other person that may reasonably be expected to have information regarding the child’s membership, citizenship status, or eligibility. Here, the grandparents’ information about the minors’ maternal great-grandmother gave the Agency a reason to believe that either the parent of the child or the child is a member or may be eligible for membership in an Indian tribe and thus triggered a duty for the Agency to inquire further, including by contacting the Yaqui tribe of Arizona.