Traumatic experience leaves a particular marker behind it. Unless given attention, it becomes like a sealed moment in a life. Though time passes and our lives move on, however much older we become, the traumatic experience remains within us.
However, if it is responded to with appropriate care (and what that means will be different for each of us), then its impact and likelihood of disturbing us in the future may be reduced. If it is ignored, by us, or by those around us, then there is a likelihood that periodically the traumatic experience will be reactivated by a chance event, by a conversation, by something someone does. And when that happens, for a period of time we may experience the disturbance of trauma again, only now it is removed from the original events that caused it in the first place. So we go through something traumatic without understanding quite what’s going on. We are re-traumatised, this can be very disturbing and hard to live with.
For this reason getting appropriate attention for traumatic experiences, however old they might be, is better than leaving yourself like a hostage to fortune and hoping it won’t disturb you again.