The Slouch Hat. The slouch hat is an object strongly associated with Australian identity. Corporal Matthew Walshaw from 4th/3rd Royal New South Wales Regiment adjusts his slouch hat before moving off to form up at the Rocks in Sydney, NSW.
This is another episode when Brian's book was mentioned. Stewie's phone number is (401) 555-0183. 401 is the actual area code for the state of Rhode Island, where Family Guy is set. Afuera is Spanish for outside. Lois mentions animal rights group PETA when Brian is speaking to the Griffins about animals rights.
Vinny is a really good match for Stewie. Where Brian was sort of a match for Stewie intellectually, Vinny is a good match for Stewie because he doesn't let Stewie get away with any crap. He'll call Stewie out on his B.S. freely.