Abstract: A resilient shirt retainer for retaining the shirttails of a garment in tucked, fully extended or deployed configuration on the body of a wearer. The shirt retainer includes a pair of narrow, elastic cross-straps disposed in an X-configuration and stitched at the center where the straps cross, each of the elastic cross-straps being covered with a pleated cloth sheath. A retainer clip is attached to each end of the cross-straps for removably securing the cross-straps to the front and rear shirttail portions of the garment. The cross-straps are deployed between the infant's legs to maintain the shirttails in a tucked or downwardly-deployed configuration.