Note: The pictures in this answer are official portraits of Yong Zhengdi Yin Zhen at different ages.
The names of Prince Yong Zhengdi and his daughters are as follows:
Four imperial women:
The eldest daughter (1694) was born on March 16th, the thirty-third year of Kangxi, and died months ago, when she was a concubine.
The second daughter (1695- 17 17) was born on the sixth day of July in the thirty-fourth year of Kangxi, and was Li (then Fang Fujin).
The third daughter (1706) was born on the fifth day of December in the 45th year of Kangxi, and died a month ago, teasing the Song family (when she was a concubine).
The fourth daughter (1715-1717) Kangxi was born on March 12, 54, and died in May, 56. She was Nian Shi, the imperial concubine of Dunsu (at that time she was a side Fujin).
Among them, only the second daughter did not die, and was later named Princess Heshuo Waike.
Ten princes:
Hong Hui, the eldest son, was born on March 26th in the thirty-sixth year of Kangxi, and died at the age of eight in the forty-third year of Kangxi. After Qianlong, he was named Prince Duan.
Hongyun, the second son, was born at the beginning of June in the thirty-sixth year of Kangxi, and died on February 29th in the thirty-eighth year of Kangxi (1July 69719 ~1March 30, 699) at the age of two.
The second son, Hongyun, was born on the seventh day of August in the thirty-ninth year of Kangxi and died on October 20th in the forty-ninth year of Kangxi at the age of 10.
The third son, Hong, was born on February 13th, 43rd year of Kangxi, and died on August 6th, 5th year of Yongzheng, at the age of 23.
Li Hong, Zi Si, Emperor Gaozong and Emperor Qianlong of the Qing Dynasty. Born on August 13th in the 50th year of Kangxi, he was eighty-nine years old.
Hongzhou, Wu Zixu and Prince Gong. Born on November 27th in the 50th year of Kangxi, he died at the age of 58.
Fu Yi was born on May 25th, 59th year of Kangxi, and died on the 13th day of January 60th year of Kangxi at the age of 1 year.
Fu Hui was born on October 9th, 60th year of Kangxi, and died on September 9th, 6th year of Yongzheng, at the age of eight.
Fu Pei was born on May 10th, the first year of Yongzheng, and died today.
Hong Yong, born on June 11th, 11th year of Yongzheng, died on March 11th, 30th year of Qianlong at the age of 32.
From above, we can see that there are many children in Yong Zhengdi. He had eight sons and four daughters before he ascended the throne. After he ascended the throne, he gave birth to two princes. Compared with his father Kangxi and his son Qianlong, Yongzheng's children are not many, but they are also ahead of the Qing emperor.
Unfortunately, Yong Zhengdi's children are too young. More than half of the previous eight sons and four daughters died. By the time he died, there were only two left: Emperor Li Hong of Qianlong and Emperor Wuzi Hongzhou.
Mainly because the reproductive health of that year could not be guaranteed. Many children died of infection after birth, and another fatal disease is smallpox, with a very high mortality rate. The vaccination technology in Yongzheng era is still immature.
Yongzheng is like this, especially for ordinary people. Ten lives, one for two, is normal, that's how it was in those days.