Generally, they were promoted to higher positions and received generous rewards. Perhaps as the emperor's wet nurse, they would definitely have a lifetime of prosperity and wealth, but there were some exceptions.
First of all, why did the concubine not let the biological mother raise the prince after giving birth to the prince, but had to find a wet nurse? First of all, if the birth mother is allowed to raise the child, the relationship will definitely be very close, and the establishment of the wet nurse is to prevent the relationship between mother and child from being too close, which will trigger a subsequent battle for imperial power. The other is to prevent the prince's biological mother from intervening in politics after the prince ascends the throne, thus disrupting the court order and causing the queen mother to listen to politics behind the curtain, or even seize power.
When it comes to repaying the wet nurse, I have to mention Zhu Jianshen and Wan Zhen'er's long-lasting mother-son love - despite the objections of all ministers, they married the wet nurse who was 18 years older than themselves as their concubine, and she responded to every request. He loved her all his life, and after his death, he stayed away from court for seven days and the whole country mourned her. Such glory and wealth is probably unprecedented in history.
Let’s take a look at how other emperors repaid their wet nurse. In the Han Dynasty, Emperor Shun of the Han Dynasty named the wet nurse "Sanyang Lord" and his son named the wet nurse "Yewang Lord". The same was true in the Tang Dynasty, which was nothing more than promotion of officials and nobility, with generous rewards. Emperor Chengzong of the Yuan Dynasty upheld the principle that women should not interfere in government affairs, so he named the nurse's husband "Shou Guogong", while Ming Renzong also named the nurse "Mrs. Xusheng Gonghui".
In addition to Zhu Jianshen, I also want to mention the wet nurse of Emperor Taiwu of the Northern Wei Dynasty. Because the treaty of the Northern Wei Dynasty established "the son will kill his mother", that is, the son must kill his mother when he ascends the throne. After losing his biological mother, the wet nurse became his only reliance. After he ascended the throne, he named his wet nurse the Queen Mother, and she always respected and loved her. However, his wet nurse was indeed a good wife and mother, and she was kind to others all her life. Until her death, Emperor Taiwu was so distraught that he ordered the whole country to mourn for three days.
No matter how powerful every emperor is, he is still dependent on others. In the eyes of the wet nurse, they will always be a child, and only true love can be exchanged for true love in return. This can be regarded as The only family affection in the cold royal family.