Isela is an 11-year-old Mexican-American girl with mild intellectual disability. During a vacation with her family, she went swimming with dolphins. A few days later, Isela awoke at night with laughing spells; during the day, she was pacing, aggressive, and had a decline in self-care and communication skills. Her parents attributed the symptoms to the dolphins. She was evaluated by a pediatric neurologist. The sleep-deprived electroencephalogram, brain magnetic resonance imaging, lumbar puncture, and thyroid function tests were normal. A genomic microarray was sent. The neurologist initiated empirical therapy for seizures with lamotrigine, which caused a rash. It was discontinued. She was then treated with oxcarbazepine followed by topiramate for several months without any change in symptoms. Comparative genomic hybridization revealed a small deletion at 14q13.1, which includes the NPAS3 gene. Psychiatry was consulted after several months of persistent symptoms. Isela seemed to be laughing in response to internal stimuli. Owing to the decline in communication and her apparent preoccupation with visual and auditory internal stimuli, Isela could not be interviewed adequately to confirm that she was experiencing hallucinations, but her laughter seemed to be in response to hallucinations. Isela was diagnosed with disorganized schizophrenia with psychosis. Risperidone was prescribed. A psychology evaluation was completed a few months later. Parents noted significant improvement after starting risperidone with reduced inappropriate laughing spells, reduced pacing, as well as improved eating, sleeping, communication, and self-care. Cognitive assessment with the Wechsler Abbreviated Scale of Intelligence-II indicated the following: verbal estimated intelligence quotient (IQ) = 70, perceptual estimated IQ = 71, and full-scale estimated IQ = 68. There was no cognitive decline compared with testing at school 4 years previously. Although psychotic symptoms were significantly improved on antipsychotic medication and function appeared to have been restored to her previous level, her parents continued to perceive a significant decline of functioning, and they continued to attribute the psychosis to swimming with the dolphins.