The Rainbow Show

S40 E14: It's a rainbow! Elmo rushes to show Rosita, but it's disappeared by the time she arrives. Is there anything Elmo can do to bring the rainbow back so Rosita can see it? Elmo has an idea—a rainbow of monsters. He gathers monsters of all different colors and somehow gets them to line up in "Roy G. Biv" order (red, orange, yellow, green, blue, indigo, violet).