Many gelada infants experience an extremely stressful life event early in their lives: new group males attempt to kill (and often succeed) dependent offspring when they become the dominant male in the unit. To prevent the complete reproductive loss, mothers will prematurely wean their offspring, which may prevent their death. However, this life-saving strategy is likely accompanied by severe consequences for offspring growth, survival, and reproduction. The SMGRP is characterizing normative infant growth, feeding, and development, and how this early-life adversity alters their developmental trajectory. Here, we use a combination of cutting edge non-invasive approaches including photogrammetry (to measure growth); microbiome sequencing (to measure gut development and immunity); stable isotope analysis (to measure transition from weaning to solid food); and urinary and fecal hormone measure (to quantify metabolic and immune outcomes).