The show has been cancelled twice, once following the second season, which caused the show to not air a new episode for a year, and the second (and longest) being between the third and fourth seasons, from 2002 to 2005.
Bonnie Swanson would seemingly be pregnant throughout most of the series. Peter even mentions in Family Guy: Blind Ambition (2005), "Bonnie, you've been pregnant for like six years, alright? Either have the baby or don't." She finally gave birth to a girl, Susie, in Family Guy: Ocean's Three and a Half (2009).
Seth MacFarlane is a fan of the Star Trek franchise, explaining the frequent references to Star Trek in the show. In fact, MacFarlane even appeared in two episodes of Star Trek: Enterprise (2001) during its final two years of production.
The Griffins always seem to have the same thing for dinner: three pieces of some kind of beef, mashed potatoes and peas. This is similar to the television show Daria (1997), where the Morgendorffer family will usually have lasagna. Coincidentally, this show and Daria (1997) have characters named "Chris Griffin".
The first part of the opening credits, where Lois plays the piano and sings with Peter, is a spoof of Edith playing the piano, and singing with Archie, during the opening credits of All in the Family (1971).
Brian is a struggling novelist. Throughout the series, everyone in the family has made jokes about his "unfinished novel". In the episode "Movin' Out (Brian's Song)", it is revealed that the title of Brian's novel is "Faster Than The Speed of Love". When he describes the story to Lois, it turns out to be a rip-off of the film Iron Eagle (1986).
Like real-life children, Chris and Meg share the facial or body features of their parents, Peter and Lois. Meg has the same hairstyle, nose, and mouth as Lois (although Lois is considered very attractive, and Meg very ugly in the show's universe) and has brown hair and wears glasses like Peter. As for Chris, he has eyes like Lois and a nose, mouth, and cleft chin like Peter. Chris has one attribute he shares with neither parent: His blond hair. However, in the early pre-production stages of the series, Lois was supposed to have blonde hair, but the creative team decided to make her a redhead. Despite the change, they chose to leave Chris' hair blond.
Believing the series to be cancelled after season two, many of the writers took on other jobs for different shows. The show was renewed for a third season at the last minute. Many new writers were used for the new seasons.
All of the high-end hotels seen on the show have Barrington in their name. Series Creator Seth MacFarlane has stated they are named after the city of Barrington, Rhode Island, a very upscale community.
"Quahog," the name of the Griffin's hometown, is also the name of an edible clam. Clams are referenced elsewhere in the show. Some examples: The bar the characters frequently visit is called "The Drunken Clam" and the strip club the guys visit on occasion is called "The Fuzzy Clam".
Throughout the series, references have been made to the fact that some characters voices sound similar due to them being voiced by the same person. In "Believe it or not Joe's Walking on Air" (2007), Peter tells Dr. Hartman that his voice sounds similar to Carter Pewterschmidt (both voiced by Seth MacFarlane). In "Guy, Robot" (2015), Carl does an impression of Archer from the television series Archer (2009), and Bob from the television series Bob's Burgers (2011), who are all voiced by the same person, H. Jon Benjamin.
Peter's phrase of choice when climaxing during sex is "Shazam!" Cleveland's phrase of choice in the same situation is "...and boom goes the dynamite." (albeit spoken in an unexcited monotone voice as Cleveland usually speaks.)
Seth MacFarlane graduated from the Rhode Island School of Design in Providence. The shell of the quahog clam (Mercenaria mercenaria) is the official Rhode Island State shell. A quahog is a pretty standard looking clam, except that it's big, about the size of a grown man's hand. Rhode Islanders like to eat them in clam chowder (not white chowder, but clear, made without milk). They also stuff the clams with a bread and clam stuffing, and serve them for dinner. The area's Native Americans, the Narragansetts, called them "quahog", which means simply "clam". They used the purple part of the shells to make wampum, which was traded by Native American tribes throughout North America.
Brought back an unprecedented second time after its amazing DVD sales (record for best selling television show on DVD), and its popularity on Cartoon Network's Adult Swim, which a few times had a higher Nielsen rating than broadcast television at that time slot.
Meg goes to James Woods Reqional (with a "Q") High School, and Chris goes to Buddy Cianci Junior High in fictional Quahog, Rhode Island. James Woods is from Warwick, Rhode Island, and Vincent "Buddy" Cianci, Jr. is the former Mayor of Providence, Rhode Island.
The original idea for titles of episodes were supposed to be based on 1940s Mystery Radio shows. This is why the first few episodes have some sort of reference to death in them. Eventually the writers of the show had to start describing the episodes to one another (rather than simply using the titles), so that idea was dropped.
Angela, Peter's boss was voiced by Carrie Fisher, most famously known for the Star Wars saga, and when this show decided to air their own Star Wars parodies, in "It's A Trap!!!" She played Mon Mothma, ironically for her role as Princess Leia.
In early episodes of the series, the rest of the family can seemingly hear what Stewie says. In more recent episodes this becomes ambiguous: at times it's unclear altogether, other times (when it's convenient for plot development) they seem to somewhat understand.
In season seven, episode fourteen, "We Love You, Conrad", Stewie tells Brian that Bruce Jenner is a woman. The show was prescient, because (now) Caitlyn's gender reassignment happened several years later, around season twelve.
In 2014. Shortly after a repeat of Viewer Mail (#10.22) was broadcast on BBC3. There was a news report announcing the death of comedian Robin Williams, who had committed suicide. In Viewer Mail (#10.22), everyone and everything that Peter touches, turns into Robin Williams, which also depicted Robin Williams making a failed suicide attempt. (#10.22) foreshadowed the real-life death of the comedian.
After the shows first cancellation in 2002, many of the shows writers would go on to create the hit Nickelodeon cartoon Avatar: The Last Airbender (2005). Including Avatar's Creator Michael Dante DiMartino.
On at least one occasion, Quagmire references a porno channel called "Skin-A-Max" (a nickname for Cinemax, due to their late night "Adults Only" programming). The name "Skin-A-Max" was first used by Seth Green in Austin Powers: International Man of Mystery (1997) , who, of course, plays Chris Griffin on this show.
Two Kraft Foods (now Kraft Heinz Company) products are the subjects of running gags on the show. The Kool-Aid Man, mascot for the beverage Kool-Aid, often breaks through a wall after multiple utterances of the phrase "oh no!", whereas he says "oh yeah!". Also, Cool Whip whipped cream is continually pronounced as "Cool Hwip" by Stewie. Additionally, before the original Kraft split into two companies, the Nabisco subdivision's Wheat Thins had an advertisement series featuring Brian and Stewie. Nabisco is now part of Mondelez International.
Seth McFarlane admitted in an interview that the opening song was rerecorded in later seasons, mostly due to Stewie's line. Too many people thought Stewie's lyrics were "Effin' cry" when he was actually singing "laugh and cry". McFarlane redid it to better enunciate "laugh."
The trivia items below may give away important plot points.
Seth MacFarlane, the show's creator, was booked to fly from Boston to Los Angeles on American Airlines Flight 11 on Sept. 11, 2001. But his travel agent had mistakenly told him that the flight left at 8:15 a.m., not 7:45 a.m. "And I had a hangover from the night before" he said. He missed the flight, notorious for its role in the terrorist attacks on the World Trade Center.
Joe Swanson originally had a son named Kevin, who was eventually written out of the series. His disappearance was later explained in Family Guy: Stew-Roids (2009) as that he had died in Iraq, though he was later brought back into the series in Family Guy: Thanksgiving (2011), where it's revealed that he faked his own death in order to escape from the war.
Before season eight began, the character of Cleveland Brown left Quahog with his son Cleveland, Jr. to star in his own spin-off, The Cleveland Show (2009). He later reappeared in season twelve when the show ended.