Good question. . .I would say that one of the last ones made was the one with Kermit interviewing the tiny bird who sang about her parents living in different trees. ("Mama's tree is over here, back there is Daddy's tree, they live in different places, but they both love me. . .") Also, I assume we're not counting Kermit's news appearance in the "hurricane" episodes! If so, then that would likely be the last one.