We examined the relationship between video-based media viewing (screen time), behavioral outcomes, and language development in 120 36-month-old children with a family history of Autism Spectrum Disorder (ASD) or Attention-Deficit/Hyperactivity Disorder (ADHD) or no family history of either condition. Participants were classified into one of three diagnostic groups: ASD (n = 20), ADHD Concerns (children with elevated ADHD symptoms; n = 14), or Comparison (n = 86). Children in the ADHD Concerns group spent more time viewing screen media than Comparison children. Increased screen time was associated with lower receptive and expressive language scores across groups. Future longitudinal studies are needed to determine the direction of effects and causality.