Expanding the clinical picture of Simpson-Golabi-Behmel syndrome. 
This report describes a 14-year-old male with Simpson-Golabi-Behmel overgrowth syndrome.  He was born via cesarean section because of macrocephaly and subsequently exhibited significant developmental delay in motor, language, and cognitive skills with mental retardation and epilepsy.  He manifests the characteristic dysmorphic ("bulldog") facial features of Simpson-Golabi-Behmel syndrome.  His molecular genetic testing has substantiated the clinical diagnosis of Simpson-Golabi-Behmel syndrome; however, he is unique in that he has mental retardation, hydrocephalus, and epilepsy, which have not been previously documented in Simpson-Golabi-Behmel syndrome in the literature.