What is the ruling regarding my grandmother and her daughter, who perform a singing act, forbid others from performing evil, and believe that the prohibition of listening to songs is less severe than the prohibition of looking at them?

The grandmother and her daughter should be advised to abandon forbidden music, and the invalidity of their argument that its prohibition is not like the prohibition of looking [at something unlawful] should be clarified. Persistence in a minor sin makes it a major sin: "No minor sin with persistence, and no major sin with seeking forgiveness." The importance of gentleness, forbearance, and knowledge should be emphasized when enjoining good and forbidding evil, as well as assessing benefits and harms, for an evil should not be replaced by something more evil than it.