title: Display child categories when click parent category in wordpress
body: <p>I'm working on a WordPress custom theme and stuck in achieving the following functionality. I don't even know is that even possible!</p>
  
  <p>I want to display child categories when I click on a a parent category and then clicking child category will bring you posts from it. Doing it in <code>archive.php</code> will be suitable or a custom template?</p>
  
  <p>Help and suggestions would greatly appreciated :)</p>