CK II - Half-sister's husband displays as cousin in notifications, 3.2.1

[dsc]

One line summary of your issue
Half-sister's husband displays as cousin in notifications, 3.2.1

Game Version
3.2.1

What expansions do you have installed?

Monks & Mystics,
The Reapers Due,
Conclave,
Horse Lords,
Way of Life,
Charlemagne,
Rajas of India,
Sons of Abraham,
The Old Gods,
The Republic,
Legacy of Rome,
Sword of Islam,
Holy Fury

Do you have mods enabled?
No

Please explain your issue is in as much detail as possible.
Playing as U-Tsang in version 3.2.1. When the notifications regarding a half-sister's husband pops up, it refers to him in the message as my character's cousin, even though there is no relationship between my character and him except for the marriage to my character's half-sister. It does not show him as my cousin when hovering over him in the character viewer. It is only in the pop-up messages that it erroneously does this. I have uploaded a screenshot showing this, as well as a copy of the save from when this occurred.

Steps to reproduce the issue.
Save file uploaded. Wait for another half-sister's husband to die, I guess?

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