Security dad is the richest man in the world. Who is Feng?

Sister of the protagonist Feng Yihang. According to the brief information of the query novel Security Dad is the richest man in the world, Feng is Feng Yihang's own sister in this novel. Before Feng Yihang became a security dad, he and Feng Yihang lived together. After Feng Yihang became a security father, Feng Chenchen was bullied at school. Every time he was bullied, Feng Yihang would bring him pain.