Innate immunity may influence the onset of affective symptoms and alter sleep patterns in chronic inflammatory conditions. Here, we tested the prospective associations between baseline serum C-reactive protein (CRP), albumin, and CRP/albumin ratio (CAR, i.e., an emerging biomarker of disease activity), and self-reported symptoms of anxiety, depression, and insomnia at 1-year follow up in paediatric inflammatory bowel disease (n = 17). After controlling for baseline values, CAR (rho = 0.591, p = 0.026) predicted anxiety symptoms, while albumin predicted both anxiety (rho = -0.687, p = 0.007) and insomnia symptoms (rho = -0.648, p = 0.012). Current findings preliminarily suggest that inflammation may influence anxiety and sleep disturbance in paediatric IBD.