Complex sentence: They are Melody's aunts and Eric's sisters-in-law and first appear in the 1989 film, performing the opening song "Daughters of Triton", in which they announce themselves in the above order.
Split into simpler sentences: They are Melody's aunts and Eric's sisters-in-law. They first appear in the 1989 film, performing the song "Daughters of Triton", in which they announce themselves in the above order.