Spoiler..
Ah duo (jinshi biological mother, first wife of current emperor) let her baby exchange with the empress child cause she foresee that her baby will die cause no doctor can look after him and there was an illness that killed babies (the current doctor at that time were mamao uncle, Ruomen) Ruomen and other palace servants are busy enough to take care of the current empress at that time so no one will pay attention to Ah Duo since she was just prince consort (the current emperor still not the emperor). The empress is also the main head of exchange babies since she hated her children cause of the pedo emperor, pedo emperor afraid of adult woman so his empress is still a child when she gave birth to the current emperor (i think the pedo emperor force himself/rape to child empress so i understand why the empress hated her children). Jinshi become eunuch cause he didnt want to become crown prince and he just know that he is the imperial brother, the current emperor made bet with jinshi that if there was born successor then he will let jinshi do what he wants so he become overseer of concubines and take care of coming hier. The emperor know his first born child been exchange and there was scene were he and ah duo having conversation about jinshi and make her the empress but Gyokuyou is already have a male child so their relationship stays like best friends. Roumen on the other hand got his knee crippled punished and got kick out of palace because Ah duo child died (truth is the emperial brother) he dont have a choice he has to take care of the child of the empress (which is jinshi now). The emperor still want jinshi to become the crown prince even there is another heir (which still a baby and might die young prown to illness)
continue..
Jinshi didnt know the truth of his birth and real parents but I do think he suspects it and he dont want to become emperor
i guess it made a little more sense, thank you for the spoilers
So for now we know that Jinshi is the emperor's brother in disguise, but it's been repeatedly hinted that he's actually consort aadou and the emperor's child that was supposedly swapped with the empress dowager when they both went into labor that night. i mean for now he's still next in line for the throne bc the emperor hasn't had the son yet. do you guys think the emperor concocted all of this to protect jinshi and that's why they had to silence and exile mao's dad? idk what's the point to this plotline tho, cuz jinshi faking being a eunuch to hide from assassination attempts is still gonna be the same bc he's next in line anyway?