How to balance stress from work when I am home with my child?

My colleagues practice the same. We have a common understanding within the department that once we have left the office, there will be no mention of ongoing work projects. We also will not contact those on leave unless it is the last and only option (i.e. the person on leave is the ONLY one with the information needed to solve a critical issue). With that, work issues are left at work and all of us can focus on our personal stuff once we leave the workplace. The rule is the same for when we are at work. We will be all focused and in "work mode" during the time spent in the office. If there is any emergency to attend to, we will take urgent leave and not let our personal issue affect our time at work. This way, we give our best and have a healthy work-life balance. Always remember that there is always work to do and you could continue the next day when you are in office. :)