First of all, if the majority of the earnings of your family come from their labor (wages, self employment, small businesses), doesn’t matter if the earnings are small or high, your family is working class.

Secondly, doesn’t matter even if you were born in a bourgeois family, socialists aren’t like Nazis that strive for racial purity. As long as you share our values, meaning you understand that we need to end class exploitation and advance for a class-less society, you are our ally. In fact, we had some bourgeois class traitors to join our ranks, like Zhou Enlai and Friedrich Engels.