Juvenile court's finding that petitioner's minor children were dependents of the court within the meaning of section 300(b), (f) and (j), and that there were no reasonable means to protect the children short of removal in placing them in Department of Children and Family Service's custody, arising from the death of petitioner's toddler daughter in a traffic accident due to petitioner's failure to secure the daughter in a car seat, is affirmed in part, reversed in part and remanded where: 1) the juvenile court properly sustained allegations premised on petitioner's failure to secure his daughter in a car seat, and there is no support for petitioner's assertion that criminal negligence must be shown to sustain an allegation under section 300(f); 2) there is sufficient evidence to support the juvenile court's findings sustaining the allegations under section 300(b) regarding the risk of harm to the children due to historical domestic violence between their parents and the mother's cognitive limitations; but 3) the juvenile court erred by dismissing the allegations under section 300(b) regarding the petitioner's neglect of his daughter which resulted in her death as these allegations are a necessary predicate to sustain identical allegations under section 300(j), which the juvenile court sustained.