Liu'er is dead in Tang Dynasty. Yi Yu's adoption to Mrs. LAN is justified. Although there is no formal recognition, the identity of Sanfang's legitimate son has been basically recognized, and Yi Yu has changed to match his mother.

Yi Yu thought that the first time she changed her name to "mother", it would be a little awkward, even awkward. But when she really lifted a cup of tea and sent it to her mother, the "mother" came out of her mouth. But after Mrs. LAN smiled, a tear came from the corner of her eyes.

if you recognize your mother, you should naturally recognize Yi Qingxue as your elder...