The premise of this trial is that a combined nutrition (eggs) and parenting behavior intervention (responsive parenting combined with the reinforcement of animal source foods and improved WASH) will synergistically result in improved child growth, development, and reduced enteric disease outcomes over and above a nutrition only intervention and standard well baby care.

This study is a 3-arm longitudinal randomized controlled trial (RCT) to compare the following groups for effectiveness in reducing young child stunted growth and enhancing overall development:1) standard well-baby care, (n=200); 2) nutrition intervention (one egg per day for 6 months), (n=200); and 3) multicomponent Grandi Byen intervention (responsive parenting, nutrition, hygiene + one egg per day for 6 months), (n=200).

Infants will be enrolled between 6-8 months of age and followed longitudinally for one year.

A disturbingly high number of young children around the world experience stunted growth and development with irreparable consequences through the lifespan. Determinants of stunted growth and development are multi-factorial, including interactions between biological, behavioral, social, and environmental conditions, yet the evidence-base is minimal for integrated approaches to tackle the interwoven factors. Our group recently found significant impacts from an egg intervention on young child growth and biomarkers of nutrition and brain development. The effects on important psychosocial indicators of child development, however, were not assessed. Building on these findings and those of our pilot study of a group-based, multicomponent intervention (Grandi Byen, Haitian Creole for "grow well"), this randomized controlled trial (RCT) seeks to examine a greater breadth of egg intervention outcomes, the synergistic effects of adding psychoeducational parenting to the egg intervention, and mediating biological, behavioral and social factors.

The 3-arm longitudinal RCT will be carried out in Cap-Haitien, Haiti, where our group has a decade of research experience, established partnerships, and a strong research infrastructure. It is representative of resource-poor urban contexts globally, where parents face common economic and environmental challenges to child growth and development. The trial will compare the following groups for effectiveness in reducing young child stunted growth and enhancing overall development: 1) standard well-baby care, (n=200); 2) nutrition intervention (one egg per day for 6 months), (n=200); and 3) multicomponent Grandi Byen intervention (responsive parenting, nutrition, hygiene + one egg per day for 6 months), (n=200). Infants will be enrolled between 6-8 months of age and followed longitudinally for one year.

The specific aims of this project are:

Aim 1 (primary): To demonstrate the reproducibility and feasibility of egg-based interventions in reducing childhood stunting, and test its impact on development. Hypothesis 1: Linear growth will be increased by 0.30 LAZ in children receiving one egg per day compared to standard care. Hypothesis 2: Children receiving the egg intervention will have better cognitive, motor and language development compared to standard care. Question 1 (exploratory): Does an egg-based intervention impact social-emotional development?

Aim 2 (primary): To investigate the incremental benefit of Grandi Byen compared to egg only and standard care groups on primary outcomes of child growth and development. Hypothesis 3: Children of mothers receiving Grandi Byen will increase linear growth by 0.10 LAZ compared to the egg intervention. Hypothesis 4: Children of mothers receiving Grandi Byen will have higher scores on child cognition, language, motor, and socio-emotional development, with an effect size of 0.36 on cognition, compared to standard care. An economic evaluation will be conducted to compare the efficiency of the interventions.

Aim 3 (secondary). To explore pathways of intervention impacts on child growth and development by delineating the additive and synergistic effects of biological (nutrient biomarkers, bone age, and enteric disease), psychosocial (responsive parenting, cognitive stimulation), and environmental (hygiene and sanitation, diet) factors.

This study expands upon this earlier work by bringing together a transdisciplinary team spanning the biological and social sciences to work in partnership with Haitian collaborators. We will merge methods and concepts to produce comprehensive perspectives on several high priority areas including social, economic and biological factors that impact child brain development and function, nutrition among infants and very young children, determinants of bone health; and traumatic stress associated with growing up in abject poverty.

Inclusion Criteria:

• Mothers/Caregivers 18 years or older of infants ages 6-8 months
• Infants ages 6-8 months
• Living in Petite Anse, Fort Saint Michel, Madeline, or similiar communities (Cap-Haitien, Haiti)

Exclusion Criteria:

• Multi-birth infant (twin, triplet, etc.)
• congenital health condition
• severe disabilities
• severely malnourished (WLZ<-3)
• child has an allergy to animal-source foods (specifically eggs, milk, or fish).

Data collected for this study will be analyzed and stored on the on the REDCap platform and on Box, a secure, HIPAA and FERPA compliant data storage and online sharing platform. After the study is completed, the de-identified, archived data will be transmitted to and stored in a secure folder on Box; other researchers, including those outside of the study, who would want to use the deidentified data will only be able to access the data following approval from the PIs. Information pertaining to data sharing with other researchers is detailed during the informed consent process.

During the conduct of the study, an individual participant can choose to withdraw consent to have biological specimens stored for future research. However, withdrawal of consent with regard to biosample storage may not be possible after the study is completed.

When the study is completed, access to study data and/or samples will be provided through the approval of the PIs.

Researchers wanting to use the data would have to contact the PIs and explain their purpose for using the data.

Raters assessing responsive parenting and child development outcomes will be blind to the condition of mother-child dyads.

For investigators, they will be blinded to participants' assigned study arms before and during handling and analysis of the data.