Bovine-derived dural substitutes are commonly used in cranial and spinal duraplasty. Although they are generally well tolerated, allergic reactions have been reported—almost all presented with eosinophilic meningitis. A 7-year-old girl with Li-Fraumeni syndrome and diffuse pediatric glioma underwent a third salvage resection in which a bovine collagen dural onlay was placed. Ten days post operatively, she developed fever, lethargy, and a subcutaneous scalp fluid collection. Cultures and imaging were negative for infection; cerebrospinal fluid (CSF) revealed pleocytosis (elevated white blood cells and protein) without eosinophilia. High-dose dexamethasone produced transient clinical and radiographic improvement, but fever and fluid re accumulated whenever steroids were tapered. Given the steroid dependence and persistently negative infectious work-up, the graft was explanted. Pathology demonstrated a foreign-body giant cell reaction without eosinophils, and the patient’s symptoms resolved permanently after removal. This report documents the first pediatric case of bovinederived dural graft hypersensitivity without eosinophilic meningitis. Clinicians should consider graft-related allergy in children who develop recurrent fluid collections and fevers after duraplasty—even when CSF eosinophils are absent and cultures remain negative and should recognize that definitive treatment may require graft removal rather than prolonged steroid therapy.