Investing in early childhood programs such as Brazil's Criança Feliz Program (PCF) to support low-income families in providing a nurturing care environment is critical to ensure that children reach their full developmental potential. We aimed to analyze the influence of the PCF on the nurturing care environment provided by families enrolled in the program in the Federal District, Brazil. A qualitative case study was conducted based on in-depth interviews with a purposive sampling of 22 caregivers enrolled in the PCF for at least six months. Eighteen subthemes emerged from the thematic analysis following the five components of the Nurturing Care Framework (i.e., good health, adequate nutrition, responsive care, early learning, and security and safety). Caregivers recognized the benefits of the PCF on children's mental health (good health) and reported challenges in providing adequate nutrition due to food insecurity (adequate nutrition). A bond between the home visitor and families was identified as critical to promote responsive parenting practices (responsive care). Caregivers appreciated the early stimulation activities provided during PCF home visits (opportunities for early learning). Access to social welfare programs, such as conditional cash transfer and food assistance, were facilitated through PCF multisectoral actions (safety and security). On the other hand, families reported not receiving support from PCF for issues such as breastfeeding, maternal mental health, and disciplinary practices. In summary, PCF enhanced the components of the nurturing care environment provided by families. However, their vulnerabilities and contextual implementation barriers may prevent families from fully benefiting from PCF activities.