Some animal studies have provided evidence that stress early in life can be linked to negative behavioral consequences like depression and cognitive deficits while other studies suggest that stress early in life may bolster resilience to future stress. This article sought to find if this early stress or lack there of had to be experienced or if resiliency and susceptibility could be inherited. To determine if susceptibility and resilience are heritable, researches used repetitive unpredictable maternal stress and newborn separation on mice. These practices created an early-life environment of neglect and unreliable care for the pups as well as stressing the mother both through separation, forced swimming, and restraint. The male pups were then reared and went on to sire their own pups which were then put through a range of behavioral tests and compared to mice without a family history of induced stress. Compared to the control mice, the offspring of stressed fathers were more goal oriented and flexible in challenging scenarios, allowing them to excel at complex tasks. These mice were also more flexible when the rules on a task they had learned changed. and performed better on tests involving survival oriented tasks. Because these offspring didn’t have contact with their fathers and the mothers were regular control mice, the behavioral changes seen in the pups must be caused by inheritance of a molecular mechanism. Not all offspring of stressed fathers performed better on the tasks, but those that did had a specific change in a receptor gene that is thought to play a role in stress responses. These receptor gene changes come about through epigenetic marks that alter gene expression in the father who passes those alterations on to the offspring through sperm. This research suggests that the life experience that someone has before their offspring are even developing can have serious implications in how the offspring reacts to stress. It is unknown if this specific alteration is associated with the y chromosome or if these results could be replicated with mothers and daughters now that the alteration occurs even while controlling for upbringing.