Changing Email in Minecraft

Hello,

I hope someone can help because I really can't find the answer anywhere. A few years ago, I set up a Minecraft account for my son. Because I didn't know any better at the time and I found the process super frustrating, I set it up with my Microsoft account email. My Microsoft account is now the parent account for both of my kids' accounts; however, the first Minecraft account is still connected to my email address and my son would be heartbroken to lose his worlds and purchases by having to start over. How can I change the email address associated with his Minecraft account and keep his user?