According to the records in the Ming History of the Duke of Qi, he was the great-grandson of Song Mugong, and his death date should be Song Mugong's death (about 785-720 BC). His position was ceded to the prince and foreigners, and his son lived in Zheng. The son here should be the eldest son and there should be other illegitimate children. These illegitimate children are likely to be divided into "Yan" food cities, and later people will take it.

Yan's family is not from Jiang's family, but from Song Gong's family. In the early years of the Western Zhou Dynasty, it was named Yan's food city in the Song State (now Shangqiu area), and later generations took the city as their surname (now surname). Yan's earliest name is. The earliest record of the Yan family is the Genealogy of the Lu family in Longtan, Fanyang, which records the Yan family, the ancestor of the Lu family (about 725-644 BC).

There is also a saying that Yan Long, the minister of the time, said that Yan was weak. Yan Long is considered to be the ancestor of the Yan family. Besides, Yan Ying is his son.

Some people say that Wei Yan is a descendant of Lu Zhong and an descendant of Lu Zhong. The fifth son of the legendary ancient emperor Zhuan Xu was named An Yang, and his descendants took Yan as their surname. During the Spring and Autumn Period, together with Gao, Guo and Bao, they became the four famous families in the State of Qi, and served as officials in the State of Qi for generations.