Recent initiatives have focused on integrating transdiagnostic biobehavioral models of clinically-relevant processes with quantitatively-derived dimensional structural models of psychopathology. Toward this effort, affiliative capacity (AFF) and inhibitory control (IC) processes hold particular promise as they demonstrate transdiagnostic utility and stability across developmental stages and multiple measurement modalities. The current study integrates across informants and modes of measurement in a sample of 1,671 5-to-10-year-olds to probe the unique and moderating effects of IC variation on low AFF in explanation of broad, empirically derived dimensions of psychopathology. Whereas no unique associations emerged for IC, low AFF was a significant predictor of distress- and externalizing-related problems. Distinct moderating effects emerged such that in combination with low AFF, high IC protected against distress symptoms specifically, whereas low IC predicted distress and externalizing problems. Results are discussed in the context of the interface of general trait transdiagnostic risk factors with quantitatively-derived dimensional models of psychopathology