More can always be said on this matter, so if anyone would like to provide a new post of their own, please don't hesitate to do so! We always welcome more insight into any matter.

For the meantime, OP, these previous posts on how incest was treated in the Middle Ages may be interesting reading:

• u/WelfOnTheShelf covers the legal side of things with canon law and the concept of affinity;
• while u/cdesmoulins has a closer look at law and the accompanying attitudes.