Xiao Ze was thinking about making use of Cheng Chu when Cheng Chu approached him on his own initiative. Even though he had been rejected many times before, he still wanted to try again.
So, after Cheng Chu had finished visiting Cheng Liangdi in her courtyard and came out, he happened to run into Xiao Ze.
Cheng Chu hurriedly paid his respects to Xiao Ze.
Xiao Ze was quite amiable, "Uncle, no need for formalities!"
Cheng Chu was startled, taking a step back in surprise, thinking how he was not fit to be called "uncle" by the Crown Prince. His sister was just a concubine of the prince.
Xiao Ze looked at him, explaining, "Uncle does not need to be fearful. I have decided to lift the ban and will request the Emperor to promote Cheng Liangdi to side consort."
As the brother of a side consort, he could indeed be addressed as "uncle."
Cheng Chu's eyes widened in disbelief, "Your Highness is going to promote my sister to side consort?"