i made a mod where the greystark have traditional claims on the duchy of whiteharbor, the county of whiteharbor and the castle of the wolf's den when they don't rule it. they also get claims to the north and winterfell if the starks lose their titles.
make sure you don't have another mod overwriting the traditional claims and the on action file.
the event may take awhile to fire you just have to wait
'A Game of Thrones' is a user modification for Crusader Kings II not affiliated in anyway with Paradox Interactive or the rights holders to 'Game of Thrones' and 'A Song of Ice and Fire'.
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