Perinatal growth vulnerability (e.g., Small for Gestational Age, SGA) poses the goal to not overlook subtle developmental susceptibilities and their impact on the parent–infant relationship. In this case study, we examined the application of a video-feedback intervention program to support parenting, the Primary Care-Video Intervention Therapy (PC-VIT), specifically developed to fit pediatric care characteristics. The case presentation details the principal steps of the intervention with the family of an SGA infant from birth up to toddlerhood. Findings for this family highlighted initial worries about the infant’s growth. Along sessions, PC-VIT held maternal anxiety and sustained parents’ abilities to recognize and talk about the infant’s developmental skills and regulatory abilities. The PC-VIT shows the powerful opportunity to limit the impact of infant growth vulnerability on the parent–child relationship and socio-emotional development. Pediatricians can prevent vulnerable developmental milestones from clinical outcomes by implementing timely and effective strategies embracing mental health and parenting-related issues.