A Concordia University study reveals that parents of children with behavioral issues, such as aggression or hyperactivity, exhibit lower heart rate variability (HRV), indicating reduced self-regulation capacity. The research, involving 80 couples with preschool-aged children, found that this association is particularly pronounced in fathers, especially when combined with marital stress. Higher HRV is associated with better stress adaptation and emotional regulation, suggesting that both child behavior and relationship dynamics play significant roles in parental well-being.