In Duck Tales, Huey, Dewey, and Louie call Scrooge McDuck, "Uncle Scrooge". They call Donald "Uncle Donald" and Donald calls Scrooge, "Uncle Scrooge".
How are they actually related to one another?
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Sign up to join this communityIn Duck Tales, Huey, Dewey, and Louie call Scrooge McDuck, "Uncle Scrooge". They call Donald "Uncle Donald" and Donald calls Scrooge, "Uncle Scrooge".
How are they actually related to one another?
According to the Disney Wiki
Huey, Dewey and Louie are the sons of Donald's sister Della Duck
Which means they really are Donald's nephews, and as mentioned on the sidebar on the Donald Duck article, Scrooge McDuck is Donald's uncle, though really he's his uncle-in-law as this relationship is through his wife's mother, Hortense McDuck, who is the sister to Scrooge.
This means Huey, Dewey and Louie are Scrooge McDuck's grand-nephews (his sister's grandchildren) and he is their great-uncle (grandmother's brother), as you can see from the infographic below.
It's likely they just went with "Uncle" for convenience, as most people aren't familiar with the term great-uncle.
Here's a duck family tree that shows how Huey, Dewey, Louie, Scrooge and Donald are related:
reff: What the duck