The dream she had at fifteen, she only shared with one person, Su Xue.
Putting aside the fact that all of these events were merely a dream, what's more, her brother hadn't accomplished anything in that dream.
Although her brother liked her, aside from that one time in a dream, he always kept his distance from her in daily life. Before her rebirth, there was not the slightest ambiguous behavior between them as siblings!
Han Jiaojiao really couldn't understand why Su Xue would go out of her way to bring up things from her dream. What was she trying to do? What did she want to accomplish by painting her and her brother in such a disreputable light, and how would it benefit her?