Among Liu Bang's four brothers, Liu Bang's younger brother Jiao Liu has the best relationship with Liu Bang. He once fought side by side with Liu Bang and made great achievements. Liu Bang became emperor again, so it is normal to be surnamed Liu. Biologically speaking, the Y chromosome belongs only to men. Men are a Y chromosome and an X chromosome, and women are two X chromosomes. Men inherit the Y chromosome from their father and the X chromosome from their mother, so their Y chromosomes must be different. So the Y chromosome is genetically different, but the X chromosome is 50% likely to be the same, so it can't be said that it is not a family. Moreover, Liu Jiao was influenced by Liu Bang since he was a child, and his thoughts were closer to Liu Bang.