The patient is a 2-year-old Caucasian boy with acute acalculous cholecystitis (AC) but none of the predisposing factors that are typically found in patients with this disease. The presentation and clinical course of the disease was typical of AC. Nonsurgical intervention resulted in resolution of the child's initial symptoms. After recurrent bouts of biliary colic over the ensuing ten weeks, further evaluations were completed. Persistent inflammation of the gallbladder was seen on computerized tomographic scans and a nonfunction of the gallbladder was demonstrated through radio-nucleotide scanning. After discussing the findings with the parents, we performed a routine laparoscopic cholecystectomy on the child. The typical presentation, diagnosis, and pathogenesis of AC are discussed.