Sasha has a different mother and Cody has a different father and they started their relationship before they knew they were related. The only real issue is passing on genetic anomalies, which may not be an issue since they aren't full genetic cousins.
For example, it is gross for a stepbrother to marry a stepsister when their parents got married when they were children. My nieces kids and her stepkids go the same school and live with her and her kids every other week. They have been raised as siblings, and any romantic relationship would be incest.
However, if an adult's mother marries a man with adult children, and said children meet each other as adults, if her daughter fell in love with his son since they had no history with each other, it would be ok if they got married. Since they had no history as siblings and there is no genetic issue, I don't see the harm.
Karen L.
Karen L.