Eighty-three low-income Mexican-heritage children (44 girls) and their mothers participated in this research. Children were observed with alternative caregivers at 14, 24, and 36 months of age using the Attachment Q-Set. Most children received regular care from infancy through preschool from relatives and childcare providers. Children had high attachment security scores with both mothers and caregivers. Child-other and child-alternative caregiver attachment security scores were independent of each other. Children whose mothers did not participate in family clusters were lowest in child-other attachment security at 14 months. More emotionally sensitive mothers and responsive alternative caregivers were associated with more secure child-adult attachments. Mothers who had more contact with relatives still in Mexico were more likely to have somewhat more positive relations between intrusive interaction and positive attachment relationships than mothers who had less contact.