If google translate translated it correctly, in the novel
I'm not sure about this one, but if I'm not mistaken, they should have been ranked quite high before since the family knew Luo family and had dealings with both the Luo family & Ou family. However, because of the Ou family, the Xu family's oldest brother & dad got killed and the family was in ruins (they were placed in jail). Only after the Luo family's grandfather asking for forgiveness (?) from the Emperor on behalf of the Xu family and asking permission for Lingyi to make atone by going to the army was Lingyi able to restore the family's reputation and make it as good as it is now.