Sometimes I will say I am, if I am "from" anywhere, from Chicago, but this is simply not true, and any "real" Chicagoan would scoff hard at hearing it. Hell, two of my major boyfriends, both "burbies"* would never let me say that. I don't even have the accent. (Chicagoans don't think they have an accent unless they're from the west or certain portions of the south side. They do, though.)
Here is what happens when two Chicago natives meet:
Native the second will challenge with: "Oh yeah? What suburb?"
Native the first will spit back the countersign, their location on the city grid: "2400 north, 3400 west."
2 will do some mental math and come up with a surprised naming of the nearby cross streets and a perjorative nickname for the neighborhood punctuated with rapid affection for the same: "Kimball and Fullerton? Murder Alley, no shit? West side represent!" and point to their sternum, following up with their neighborhood, coordinates, and the high school they went to, the high school they were supposed to go to, whether the neighborhood has gentrified or gotten "worse," and where they got Italian ices growing up (even though, AFAICT, all Italian ices came from the same distributor. I think it was a way to further distance from suburbanites and non-natives: you didn't walk to get Italian ices on humid summer nights in the suburbs, you went for Homer's or Rainbo Cone or Al Gelato, all ice cream places, and you had to be exposed to it young for it to have emotional weight). "[sternum point]Rogers Park! I was supposed to go to Senn, but I went to ETHS. Except for my junior year. Junior year I went to St. Gregory's. Man, I tell you, ten years ago... oh, right. Calo's, but not the Calo's by Saint..."
Native son # 1 will then run his tongue over his teeth and ask the real question: "What hospital were you born at?" (Chicagoans are born "at", never "in" hospitals.)
And by some surreal miracle of time, space, and the Dunbar sphere, it will turn out that native # 1's mom knows one of the labor nurses present at #2's birth, who will, if pressed, remember some odd detail about it, usually some sartorial quirk of the father.
I'd say that this prevents moles from entering Chicago society, but I suspect the nurses are the moles.
If this is a sim, hats off to the designer. That's quality world-building, that. (I love to see to see this sort of exchange in spec fic universes, even to the "Brooklyn/ Queens" in the ACW movie...)
*I don't think anyone would ever say the word "burbie" in front of an actual person from suburban Chicagoland. It would be too cruel, as the image that evokes for Chicago natives are the party girls from Pivot Point beauty school or denizens of John Hughes movies bitching about parking at Ravinia, and if that isn't the most depressing damn thing...