In social animals, immaturity represents an important phase in life history in which physical, motor and social development mature. Immaturity is a crucial phase to understand for effective population management. The blond capuchin monkey (Sapajus flavius) is an endangered species endemic to the northeast of Brazil and is restricted to a few fragments of Atlantic Forest and Caatinga. Though there is a growing body of knowledge about the ecology of this species, descriptions of specific aspects of social behavior, particularly parental care, are scarce and are usually either secondary to the main study or are anecdotal. This study intends to document the forms of infant and juvenile care in a group of free-ranging S. flavius inhabiting an Atlantic Forest fragment in northeast Brazil. Data were collected from February to September (excluding August), 2021, resulting in 294.4 contact hours with the group, totaling 112.6 hours of direct observation (n=1105 focal samples). Behavior was collected using the focal animal method, with scans every minute to note the number of neighbors at 1 and 5 m, and which strata the animal was on. We analyzed whether ecological factors like fruit productivity, season, forest strata, and distance to forest edge influenced the form of care given to immatures, and how care changes according to different age/sex classes. In terms of direct care, a female literally carries most of the burden, being the ones transporting the immature 93% of the time, while older juveniles and adult males carried youngsters far less (5% and 2%, respectively) and most often sharing food. They are also the class that most grooms and shares food with immatures. Females with infants are the most attractive group member, as they are the most groomed and most often followed class and are seen more than expected by chance as neighbors at 1 and 5 m from almost every other age/sex class. Young immatures receive significantly more direct care than older juveniles. Males provide indirect care mostly in the form of producing scraps for scavenging, tolerating juveniles scrounging on their food, and maintaining proximity to females carrying infants and young juveniles, being seen near young juveniles and females with infants more than expected by chance (1m: χ²=2167.9, p<0.001, R2adj=12.5 and 7, respectively 20.6; 5 m: χ²=2301.2, p<0.001, R2adj=20.6 and 10.8, respectively), which could represent a form of protection from predators. The upper canopy does not seem to be perceived as more dangerous than the middle substrates, as grooming and nursing rates were high in this stratum, as opposed to the ground, where these behaviors were seen far less or not at all. Fruit productivity was slightly positively correlated with nursing frequency, but not with grooming frequency. Overall, our results corroborate with what has been inferred for this species in terms of direct care for immatures and support the fact that there is extended care up to the first year of the immature. Additionally, data on proximity indicate that males may play an important role in escorting females with infants throughout the day.