Just wanted to add another curiosity on Gilbert Grape: During filming, Lasse Hallström taught Johnny some swedish, most specifically the phrase "Jag har en liten råtta i halsen", meaning: I have a little rat in my throat. A phrase Johnny later put into good use when meeting the press at the premiere in Stockholm, Sweden.
Johnny and his crazy sense of humor. I bet he must had laughed a lot trying to speak in Swedish.
Thank you dear anonymous for your contribution!