Upgrading themes when there is a child theme

I have built a site using a premium theme, ENFOLD by Theme Forest, and I've figured out how to create a child theme, and all is working fine. Now, there is an update to the Enfold theme, and I've never upgraded a theme, especially when I have a child theme activated.

Can you tell me if there is anything I should know before upgrading the original Enfold theme? Do I need to activate the parent theme first before updating, or not?

Thank you so much for your help.
The site is live, so I don't want to mess it up. I wouldn't know how to fix it if I did. ;-(

thank you,
elizabeth