An 8-month-old Baby Girl with Slight Drooping of Left Upper Eyelid.

An 8-month-old baby girl, who accompanied her sister with an eye problem, was incidentally noticed to have smaller left eye compared to the right. The mother said that it had been present for 2 months. The child showed no detectable focal neurological deficits. Her vision was age appropriate in both eyes. A slight left-sided ptosis was present. Her eye movements were full in both eyes and there was no evidence of strabismus. Bilateral fundus examination was normal. The child had anisocoria (left pupil being smaller than the right one) and left hemifacial anhidrosis, which prompted the diagnosis of Horner's syndrome. Magnetic resonance imaging of her chest showed a mass lesion in the apical region of the left lung which was later excised and found to be a neuroblastoma. This emphasizes the importance of having an eye on the siblings of children who come to the hospital.