Colorectal carcinoma is a well-known malignancy in adults. However, it is rare in children. Besides, it also has different behaviour in paediatric age-group and usually presents with non-specific symptoms like abdominal pain, weight loss, and anaemia. This usually leads to delay in diagnosis. Adenocarcinoma in children has unfavourable tumour histology (mucinous subtype) and advanced disease stage at presentation which lead to poorer prognosis in children. Family history, genetic typing and sibling screening are essential components of management as this malignancy is frequently seen associated with hereditary syndromes. We describe a case of unusual presentation of rectal carcinoma in a 12-year-old girl.