Minecraft Realms issue with child account.

Here is a link about issues with joining relms with child accounts. Minecraft Realms

Is your Microsoft account set up as an childs account?

if not check these links

https://support.xbox.com/en-US/games/game-titles/minecraft-realms-overview

https://help.minecraft.net/hc/en-us/sections/360004954931-Minecraft-Realms

I have a Xbox Game Pass and for Minecraft the child account has the realm plus 2 users.

Hi Alex,

Thanks for reaching out to us in the forums for this issue with Minecraft Realms on the Nintendo Switch. Based on the message you received, it may be possible that your account doesn't have the correct permissions to access online multiplayer across different
devices.

Is your account a child or adult account? Players under 13 years old will have online multiplayer disabled by default with Minecraft and
won’t be able to join Realms or servers unless a parent changes their account settings.
For help with changing these account settings, you will need to change your
Privacy and Online settings of the Xbox Live account.

For further information on this and other information related to Minecraft Realms or Minecraft on the Nintendo Switch, I recommend the following support articles:

Minecraft Realms

Minecraft for Nintendo Switch FAQ

I hope that this information helps out!

Hi there! This is Ronnie, an independent adviser.

Nice to meet you and I hope you are having a great day!

I understand you need help on having your daughter play realms.

If your daughters account is already added as a family member on your family under your account, you can change these privacy and online safety settings here:

https://account.xbox.com/settings

Make sure you are logged in to your account (organizer of the family) then allow everything through privacy and online safety after selecting the gamertag of your daughter on that page.

If she has not been added on your family yet, you may add her here:

https://account.microsoft.com/family

Once you have done submitting the changes, wait for a couple of hours and she should be able to access online.

Hope that helps!