In the world of Who Framed Roger Rabbit, it's stated that there was no known way to kill a Toon until Judge Doom came up with the Dip. But near the end of the movie, Eddie Vallant does a song and dance routine that "knocks the weasels dead", complete with angel wings and harps. He does this because earlier in the film, Judge Doom and Smartass (yes, that's really his name) admonished the other weasels for laughing uncontrollably, saying that they could, in fact, die laughing (like their hyena cousins).
Did the weasels die laughing? Did their hyena cousins? Or are the "angel wings" just an affectation that will wear off eventually?
Note that these questions do not apply to Smartass. He was kicked into a large vat of Dip. He ain't coming back, folks.