Princess calling birth mother "sister"

One of the hardest thing to adjust to in this drama is how historically accurate the titles, names, honorific are. The most obvious example is Emperor not being called "huang shang" (皇上) or "bi xia" (陛下). He is "guan jia" (官家 literally means Head of government officials). Not being a history buff, I only have ???? stamped across my forehead every time I hear that term.  

The other oddest thing in this drama is Princess Huiru calling her birth mother "jie jie" (姐姐 literally means big sister). I can understand her not addressing her birth mother as "mother" because her mother's low status in the harem. The Empress is, by all sense of legal definition, her "real" mother. But to call one's birth mom "big sis"? That is really pushing it. 

So I did some research.  Turned out, there was a period in Song Dynasty when the royal family's titles and hierarchies were all out of wack.

And it was all because of 2 things: Marriage and age. 

It was a political necessity to have marriage alliance between the Emperor's children and the government officials' children. Problems arose when the Emperors' princesses were too young and the officials' sons were too old to be married to each other. So the solution was to marry the princesses to the grandsons. But that created a hugely royal problem. Because the marriage would make the government officials a generation higher than the Emperor, and thereby putting them in a higher social hierarchy than the Emperor. And as you know, no one can be above the Emperor. 

Hence, the workaround. 

Unmarried princesses were bumped up a generation higher. When they marry, their husbands got bumped up a generation too. That meant the newly weds were the same generation as the husbands' parents and the Emperor the same generation as the husbands' grandparents (aka government officials). Follow me so far? 

Now back to the royal family. 

The Emperor and Empress were still father and mother, but everyone else dropped a generation when standing next to the princesses, including Princess Huiru's birth mother. That means... Princess Huiru and her mother are the same generation. And how do you address older female of the same generation? Big sister.  

 Lady Unagi:

This is my opinion. First the emperor to be called "guan jia" 官家 was true in that dynasty song era instead of  "huang shang" (皇上). 

For Huirou called her mom with  "jie jie" 姐姐 that's the imperial thing to call concubine mother with it. Huirou never said mother to The Empress.. she called her 娘娘"niángniang" it means her royal highness. 

It was such a nice research. Thank you

Actually, Princess Huiru calls the Empress, "孃孃", which is different from the royal title "娘娘". 孃  in this sense is "mother." In a broader sense, it can also mean "aunt".  

 RSMasterfade:

Not an expert on this, but according to the original novel, it's common practice at the time among those who can afford concubines that children would call the wife 'mother' and the birth mother (if different) 'big sister'. 

That's interesting. I must've missed when I was watching Legend of Ming Lan.

 RSMasterfade:

Not an expert on this, but according to the original novel, it's common practice at the time among those who can afford concubines that children would call the wife 'mother' and the birth mother (if different) 'big sister'. 

I have the same understanding as yours.