Su Xinyi remembered the words His Highness had said to her last time, She knew she wanted to have a good life with His Highness, but she hadn't expected His Highness's thoughts to deviate somewhat from hers.
He told her about how Mrs. Fo endured in silence for over a decade in front of Prince Yi and Princess Prince Yi, saying that long companionship can change a heart, wasn't this implicitly telling her that, if someone else truly entered the Eastern Palace, over time, even His Highness himself couldn't guarantee that he wouldn't change his heart?
Even if Prince Yi liked Princess Prince Yi so much, didn't Mrs. Fo successfully sow discord between them in the end?
If Princess Prince Yi had lived a few more years, wouldn't Yanling have received the title of Prince Yi?
So was His Highness circuitously telling her that not only must such incidents not occur, but any signs of them should be nipped in the bud?