This study examined the emotional and behavioural functioning of siblings of children with special health care needs identified in the Longitudinal Study of Australian Children (LSAC). Of the 106 siblings identified, 15-52% had emotional and behavioural difficulties in the at-risk or clinical range on the parent-reported Strengths and Difficulties Questionnaire (SDQ) subscales when aged 4-5 (wave 1), 6-7 (wave 2), 8-9 (wave 3) and 10-11 years (wave 4). After controlling for differences in socio-economic position, siblings had significantly higher difficulties on all subscales than their peers without a brother or sister with a special health care need at most time points. Latent growth modelling revealed little change in emotional and behavioural symptoms for siblings across childhood, while behavioural symptoms decreased for their peers. These findings suggest that some siblings are at heightened risk of emotional and behavioural difficulties across childhood, underscoring the importance of assessing and promoting the wellbeing of all family members when providing services to children with special health care needs.