Pipelines for Project Management: Moving a relationship across apps

To sort through our COVID-19 Projects by funding source, I need to move records from one app to another. I also need to move projects and their associated tasks. I currently have a pipeline that runs on a specific field at the project level. I want to extend that to move also the related tasks and their details (such as task description and status).  In the receiving app, I have it configured to match the fields for both the tasks and projects, so I would just need to know how to move the relationship as I move the record (the receiving app already has a relationship between projects and tasks)  Does anyone know how to do that?

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Nada Mousa
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