The juvenile court erred by placing minors in a guardianship with the stepgrandmother with criminal conviction instead of proceeding to 366.26 hearing. At a dispositional hearing, the juvenile court appointed the minors’ stepgrandmother as legal guardian for five of the minors. The agency appealed from the order, contending that the juvenile court erred when it relied on section 360, subdivision (a) to appointment the stepgrandmother as the legal guardian instead of proceeding directly to a section 366.26 hearing. The appellate court agreed that the juvenile court erred and reversed the order. The mother in this case had already received 18 months of reunification services, and services for both fathers had been terminated. At this stage, the juvenile court’s only option was to proceed to a section 366.26 hearing as required by rule 5.565(f). Further, the juvenile court erred when it relied on In re Summer H. (2006) 139 Cal.App.4th 1315, to justify its decision to place the minors with the stepgrandmother, despite the prohibition of section 361.4. The Summer H. analysis does not apply to the disposition of a supplemental petition. The trial court was obligated to comply with section 361.4 when it placed the children in a legal guardianship, and it erred when it failed to do so.