The Social Genome Model (SGM) is a lifecycle model that uses data from three longitudinal surveys to track a matched panel of individuals from birth to age 30, with projected estimates of earnings through age 65. The goal is to understand how private and public policy interventions could improve lifetime outcomes of children and young adults. The model also allows researchers to track patterns of development across different gender and racial or ethnic groups. This technical document outlines the process of creating the SGM Early Childhood version of the model. This version of the model is an alternative to the SGM version 2.1 as it includes additional data for the early childhood life stages. (author abstract)