Examine associations between biologic factors (genetic, epigenetic, transcriptomic, metabolomic) and environmental factors (family psychosocial dynamics, environmental allergens, diet, microbiome) in developing children, and their relationship with health and disease over the lifespan.

Depending on the age your child is when they are enrolled into the study will determine their designated enrollment group (Cohort 1, Cohort 2, Cohort 3, or Cohort 4) to determine how many study visits are required to complete participation in the study. For Cohort 1 participants (for infants enrolled at age 5-50 days): -9 study visits total -Each study visit includes surveys that assess your child's growth and development that you can complete via your email -Each study visit includes at minimum a saliva swab sample **Infants will be asked to collect a stool sample for 3 study visits -Optional mother participant for breast-feeding mothers who will agree to provide a small breast milk sample for 3 study visits. For Cohort 2 participants (for children enrolled at age ~24 months): -6 study visits total -Each study visit includes surveys that assess your child's growth and development that you can complete via your email -Each study visit includes a saliva swab sample **Children will be asked to collect a stool sample for 1 study visit For Cohort 3 participants (for children enrolled at age 5-7 years): -4 study visits total -Each study visit includes surveys that assess your child's growth and development that you can complete via your email -Each study visit includes a saliva swab sample For Cohort 4 participants (for children enrolled at age 12-14 years): -2 study visits total -Each study visit includes surveys that assess your child's growth and development that you can complete via your email -Each study visit includes a saliva swab sample

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