The only extant historical source about her life is her biography written by her maternal grandson, Xiahou Zhan (夏侯湛), who was a notable scholar and official of the Jin dynasty.
[4] She is best known for giving advice to her family members and relatives during significant events in the history of Cao Wei such as the Incident at the Gaoping Tombs and Zhong Hui's Rebellion.
Xin Xianying's ancestral home was in Yangzhai County (陽翟縣), Yingchuan Commandery (潁川郡), which is around present-day Yuzhou, Henan.
After the fall of the Eastern Han, Xin Pi continued serving in the Cao Wei state during the Three Kingdoms period and his highest appointment was Minister of the Guards (衛尉).
Yang Dan, who was from Taishan Commandery (泰山郡; around present-day Tai'an, Shandong), served as the Minister of Ceremonies (太常) in the Wei central government.
"[9] When Xin Pi told his daughter about it, she sighed and said: "A crown prince will succeed a ruler and inherit his kingdom one day.
"[10][2] Xin Xianying was essentially implying that Cao Pi should express sadness because his father must die before he can become the next ruler, and that he should feel intimidated by the fact that he would have to shoulder the heavy responsibility of ruling a kingdom.
On 5 February 249,[11] when Cao Shuang accompanied Cao Fang on a visit to the Gaoping Tombs, his co-regent Sima Yi took advantage of his absence to stage a coup d'état and seize control of all the armed forces in the imperial capital Luoyang.
Before Emperor Ming died, he held the Grand Tutor close and entrusted him with state affairs.
Although Cao Shuang too was entrusted with this responsibility along with the Grand Tutor, he has been monopolising power and acting autocratically.
Xin Chang heeded her advice and followed Lu Zhi out of Luoyang to join Cao Shuang.
After Cao Shuang had suffered death, Jiang Ji said to Sima Yi, “Xin Chang and Lu Zhi and others who had been of his party had forced the gate and joined the rebels.
“They are righteous people who serves their master faithfully,” said Sima Yi, and he even confirmed these men in their offices.
"[19] Xin Xianying then cautioned Yang Hu: "Zhong Hui is wilful and unbridled in his ways.
"[20] When Zhong Hui was about to leave for the campaign against Shu, he wrote to the Wei imperial court to seek permission to bring along Yang Xiu (羊琇), Xin Xianying's son, as a military adviser.
Their first son, Yang Jin (羊瑾), served as the Right Supervisor of the Masters of Writing (尚書右僕射) in the Cao Wei government.
[28] Xin Xianying and Yang Dan's second son, Yang Xiu (羊琇), continued serving in the government of the Jin dynasty after the end of the Cao Wei state, and became a Regular Mounted Attendant (散騎常侍) under Emperor Wu, the first Jin emperor.