Combined Text Field up to Grandparent Table

Is there a way to get a combined text of the grandchildren up to the grandparent, without creating a direct relationship between grandparent and grandchild?

I can't use a summary field twice, as it works to bring it up to the parent, but then the next summary up to the grandparent wont work correctly. Unless there is some intermediate tricky step with formulas I can use?

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Mike Tamoush
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