One MSI running two MSI

Hi...
I need to create ONE MSI using WISE. The parent l MSI is depended on another MSI, so I need to run the second MSI within the parental MSI. What is the best way to do this. I cannot create two different MSI, also, I am aware of some of the issues with nested MSI, like upgrade or uninstall.
When client wants to uninstall the parent MSI, it needs to uninstall the second MSI as well.

So i am trying to find the best way to make the MSI without having any upgrade or uninstall issues in the future.

Thank you for your help.  

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