Other research continues to accumulate, indicating that the early years are critical in the development of intelligence, personality, and social behavior. For example, children are born with physical, social and psychological capacities allowing them to communicate, learn and develop. If these capacities are not recognized and supported they will wither rather than improve. Children whose caregivers interact with them in consistent, caring ways will be better nourished and less apt to be sick than children who do not receive such care. Establishing a loving relationship in the early months of life has been shown to affect the ability later in life of a person to love and to establish permanent relationships.
Longitudinal studies demonstrate long-term effects with a variety of intervention programmes.
Improving a young child's health and nutrition, and providing opportunities for stimulating interaction and early education can bring a high economic return to society as well as to the individual. Investment in early development can help to reduce economic and social inequities. This reinforces existing differences. Indeed, there is increasing evidence that children from more disadvantaged backgrounds can profit more from good early childhood programmes than more advantaged children Inter-generational effects. To the extent that programmes of early childhood care and development affect subsequent education, the evidence suggests that they will also have an effect on fertility and population growth.