"Devo gomitare!" in lieu of "Devo vomitare" (Sebastian & Lucas)
"Che buono questa cadrega!" (Lucas)
"Papaaaaa, voglio una Ferraaaaarrriiii" (Sebastian, in his long whiny voice)
"Uffffffaa" (Sebastian, in replacement of the F-word which he just stopped using!?!?!)
"Mommy, if you say the f-word, I'm going to call the policeman." (Lucas, after hearing me curse on the phone with a friend)
Using "why" instead of "because". Example: "Lucas, why did daddy pick you up from the pool today?" Answer: "Why when I big, I gonna be a fireman!"
They make me laugh at least a few times a day.