This study identified a possible autistic spectrum subtype expressed through family psychopathology coupled with autistic probands’ cognitive functioning (i.e., an endophenotypic profile). Participants included 24 children with Autism Spectrum Disorder (ASD) and 49 children with Learning Disorder (LD). There were significantly higher rates of Mood and Anxiety Disorder in first degree maternal relatives and of LD and Attention-Deficit Hyperactivity Disorder in first degree paternal relatives of ASD probands. Significantly higher visuospatial functioning was noted in all ASD probands for which there were higher rates of Mood Disorder on the maternal side suggesting a possible marker for an ASD subtype and indicating that maternal psychopathology may have a neuroprotective effect on visuospatial functioning.