
I believe that they are talking about the first prince and his problem with fertility that Aheng helped treat, so they are giving her gifts because he can now have children. It is also possible that there was an error and the first prince became crown prince in translating, or he is just the crown prince for show when ML's legs healed and ML will be crowned later ors something.

I stop reading the novel because even though the story is cool and somewhat good but the pacing and fillers are too much it bored the hell out of me.
Mostly the repetitive villian: girl falls for prince, then gets mad at aheng, then plots to bring her down, then failed or people underestimate aheng, then they try to bring her down, then they failed. This has been going round and round throughout the story.
When I see another like the above mentioned villian I just skips until the part where they move on again or has a plot development.
Which one is the crown prince again? Who are his side consorts and concubine again???
Also I thought the Emperor favored our ML then why would there be a crown prince????