According to details written in the early script of the show's pilot episode, Fiona Gallagher was originally supposed to be very average-looking and overweight, with rattier clothes and messy blonde hair; a huge contrast from the slender, brunette beauty (Emmy Rossum).
A unique presenting trademark is a main characters' breaking the fourth wall at episode beginnings, inquiring as to why the viewer supposedly did not view the previous episode before recap flashbacks with unaired scenes.
Allison Janney played Sheila Jackson on the original pilot, but when the producers decided to expand the role, Janney had to drop out because she was a full-time regular on Mr. Sunshine (2011), so Joan Cusack was cast.
Each child, aside from Liam, identifies with the behavioral roles of children of alcoholics. There is the perfect child or the hero (Debs). There is the rebel or the scapegoat (Carl). There is the clown or the mascot (Lip). There is the lost child or the loner (Ian). And there is the caretaker (Fiona).
Shameless is an American remake of a British show. The UK counterpart (same title) is set on the Chatsworth council estate, a fictional borough in Manchester. It originally ran from 2004 to 2013 for 11 seasons and 139 episodes.
During the show's third season Emmy Rossum had the show's script writers give Justin Chatwin a fake scene in which he told his father he was gay. The crew members revealed it was a prank on camera. He played a gay son to a homophobic father on Weeds.
Originally there was a scene on the season 3 finale where the Brasilians played hockey with Jimmy's head, an clear indication to the audience that the character had been killed. They even made a fake head after Justin Chatwin, but they chose not to show the scene in case they changed their minds about killing the character. Creator John Wells said publicly that the character was dead, but ended up bringing Chatwin back for a few episodes to write him out of the show properly and wrap up his storyline with Fiona.