Hi Partner,
You could use Connect to show both primary contact and child contacts in the same subgrid with different tags.
1.Manually action.
For example, I have a Account Datum with primary contact Rene and child contact Susan.
a).Create 2 connect roles in Business Management for different contact tags in subgrid.
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Here I created "Primary Contact" and "Contacts".
b).Create a new conncet from account to contact.
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c).Choose the primary contact Rene in "Name" and "Primary Contact" in role.
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Save and close.
Do the same thing for another contact "Susan" and choose "Contacts" for its role.
Then open the related view "Connections".
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Here you can see primary contact and child contact are in the same subgrid with their tags.
2.If you want to apply this function to all your account records, you could use Power Automate to create an on-demand Flow.
a).Create a Common Data Service button Flow.
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b).Add a create records action, set the entity to "Connections".
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In "Role To", you should fill in the record Id of "Primary contact" role.
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c).Add a list records action to list all the child contacts and set their connections.
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d).Add a create record action. Here add the "Contact" role ID in "Role To" field.
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Then we can select one or multiple records and trigger this FLOW manually.
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The last thing is to create a view for connections to show this Account - Contact connections only.
Best Regards,
Leo