Parental practices and environmental factors can impact a child’s development and, consequently, functionality. The objective is to assess the parental practices and environmental differences in healthy and at-risk infants at 3–6 months of age living in upper-middle (Brazil) and high-income (Italy) countries. A total group of 115 infants was identified and classified into four groups: healthy Italian infants (H_IT); Italian infants exposed to biological risk factors (R_IT); healthy Brazilian infants (H_BR); and Brazilian infants exposed to environmental risk factors (L_BR). The dependent variables were parental practices and environmental factors, which were assessed through a semi-structured interview and the “variety of stimulation dimension” from the Affordances in the Home Environment for Motor Development—Infant Scale (AHEMD-IS) questionnaire. Descriptive analyses, a multivariate analysis of variance (MANOVA), and correlation tests were applied. Regarding the environment and parental practices, the mother’s age, maternal and paternal education, civil status, and variety of stimulation showed significant differences among the infants living in Brazil or in Italy. There were strong dissimilarities in parental practices and environmental factors among infants living in low/upper-middle and high-income countries. Since the home environment is the main stimulus for infant growth and development, our results are meaningful for providing knowledge about these two different cultures.