The assessment of acute vertigo in childhood is often challenging, but fortunately a central cause is rarely identified. We present the case of a 7-year-old boy who developed, after a mild head trauma, a rotary vertigo associated with nausea and vomiting. A posttraumatic peripheral vestibular dysfunction was first suspected but not confirmed by an otoneurological evaluation. When subtle neurological signs were elicited, a brain magnetic resonance imaging was promptly requested. This showed a small infarct on the lateral posterior left part of the medulla oblongata of the brainstem, typical of Wallenberg syndrome. Vascular imaging was normal and no defined etiology was found. The child was started on prophylactic acetylsalicylic acid. The rapid disappearance of vertigo was noted. On follow-up at 6 months, there has been no recurrence and neurological examination was fully normal. Our case extends the differential diagnosis of acute vertigo in childhood that rarely includes the possibility of a brainstem infarct whose recognition through appropriate clinical examination is nevertheless capital for appropriate investigations and management.