The current study utilized survey data to determine if respondent characteristics and inter‐rater agreement on measures of important relationships were associated with resilience among child welfare‐involved youth. Youth and key adults (e.g., caregivers or caseworkers) each completed a multidimensional survey of youth well‐being. Both responded to measures of sibling and peer relationships; youth also completed a brief resilience measure. Inter‐rater agreement for sibling and peer relationship constructs were established through independent samples t‐test, Pearson correlation coefficient, Cronbach's kappa and double‐entry intraclass correlation coefficient. Linear regression models then examined associations of respondent and dyad characteristics to inter‐rater disagreement, and inter‐rater disagreement to youth reported resilience. Post hoc analyses probed interactions for respondent characteristics and inter‐rater disagreement to youth resilience. Results indicate key adults overestimated the quality of youth's sibling relationships, and inter‐rater disagreement was highest when the youth was older and the adult was a caregiver. Sibling rater disagreement was associated with higher youth reported resilience. For peer relationships, significant inter‐rater disagreement was not observed. Higher relative disagreement, however, was associated with lower youth resilience. Findings suggest levels of inter‐rater agreement may be an important consideration when assessing the well‐being of youth in out‐of‐home care.