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There are many topics to discuss in this fine research. My attention goes to the association between younger age and sleep related death reported in those deaths remaining unexplained after structural autopsy. SIDS and SUDEP have parallels worth considering. Sleep affects heart rate, blood pressure, respiratory rate, and muscle tone, while depressing protective reflexes to hypoxia and hypercapnia. Relevant to SIDS, autonomic regulation matures during infancy, with decreased baroreflexive responses and arousal during the peak ages for SIDS. Heart rate variability changes as a function of age and sleep state during fetal and early life, with greater variability noted in preterm infants at greater risk for SIDS. SUDEP is also associated with sleep, and there is much research on sleep state and seizure activity. Finally, cardiac channelopathy genes are also expressed in brain regions influencing autonomic control. How are we to understand this reported association between cardiac death and sleep?