Divi Child is a WordPress theme. Whenever you need to make modifications to any WordPress Theme, it is best practice to create a child theme that inherits the design and functionality of that parent theme. One important reason to create a Сhild theme is to preserve the modifications you make when updating the parent theme. Whenever you update Divi, all of the theme files are updated so if you have made any changes to these files, those changes will be erased.
How To Use Divi Child Theme
2) Donwload Divi Child theme and unzip, copy and paste folder /divi-childup/ into WordPress folder */wp-content/divi-childup/.
3) Activate the Divi Child theme in your admin panel
Note: Keep in mind that you don’t need to activate the parent theme in order to use the child theme