Extension:
Raising brothers and demons is a network term that refers to brothers and sisters in families with many children. Usually, due to the influence of family, they will contribute to their younger brother at no cost.
Because children born in a noble family have been influenced by family values since childhood, they have been helping him and even supporting him all their lives. Hence the name "Brother Helper". Maybe it is named because, like Voldemort, they all have strong beliefs about some wrong things.
Citation example
First, help my younger brother: I only have such a younger brother.
Second, help the younger brother: Who let me be the boss of this family?
Third, help my brother: that's my brother. what can I do? I can't ignore it.
Baidu Encyclopedia-Defomo