What Only Firefly Lane Novel Fans Noticed About Season 1

The hit Netflix series Firefly Lane was based on a 2008 book of the same name by Kristin Hannah, and even though the book's author was a co-executive producer on the television series, fans of the book couldn't help but notice some differences between the two mediums. Since the TV series ended before the events of the novel on which it is based, there's a possibility some changes were made on purpose to extend the series further. However, while many significant events and characters were added to create more drama, some were also left out completely.

Both the book and TV series follow the lifelong friendship of Tully Hart (Katherine Heigl) and Kate Mularkey (Sarah Chalke) over multiple decades, starting when they were teenagers and culminating in adulthood. Even though fans of the show are still awaiting a season 2 announcement, it's fun to speculate what will happen based on the differences — so far — between the book and Netflix show.

The timeline isn't chronological on the Firefly Lane TV show

One of the biggest differences between the book and TV series is that, while the book is told in chronological order, the series jumps between timelines, showing Tully and Kate in the 1970s to the early 2000s. The two friends meet in 1974 while in the eighth grade, but each episode jumps between decades and situations as needed to explain or reveal major life events in the two friend's lives. For example, one episode portrays various holidays through the years while another highlights the different weddings they've experienced.

While this format helps viewers learn more about the characters, it also makes it difficult to squeeze in minor storylines from the book besides major life events such as marriages, births, and deaths. However, it also keeps material from the book available for future episodes. The good news is that author Kristin Hannah wrote a sequel to Firefly Lane called Fly Away, which should provide more than enough material for a second season should it be greenlit.

Kate's brother Sean gets a storyline on the show

Sean Mularkey is Kate's brother, and on the show, he is played as a teenager by Quinn Lord and as an adult by Jason McKinnon. As fans of the book know, Sean was a minor character who is mostly only mentioned and is known to have several girlfriends. He was also Kate's younger brother. In the Netflix series, Sean has been aged to be Kate's older brother, and he becomes a supporting character whose storyline is more developed. 

Early in the TV series, it is revealed that Sean is a closeted gay teenager. When Tully catches him kissing his friend Robbie, she keeps his secret, not even telling her best friend Kate. This creates a bond and friendship between Tully and Sean that carries throughout the series. As a young man, Sean serves in the military and later has a live-in partner named Richard, who is only mentioned and never shown. It is later revealed that Richard died, and the implication is he died from AIDS. 

When Sean marries his pregnant girlfriend Julia, Tully tries to convince him before his wedding that he's not being fair to himself or Julia. Sean declares he wants a family and references a "plague" that's killing gay men. Sean eventually comes out to his sister, and later, he reveals his sexuality to his wife, who kicks him out.

Johnny and Kate stay married in the book

Kate's family situation is also different in the book and TV series. In the novel, Kate and her husband, Johnny, have three children: a daughter and twin sons. While they experience problems in their marriage, the couple never divorces and remains loyal to one another throughout the book's events. On the Netflix series, however, Johnny and Kate are in the midst of a divorce and only have one daughter, Marrah.

In both formats, Johnny is a foreign war correspondent who gives Tully and Kate their first jobs as journalists. He remains a producer on Tully's show The Girlfriend Hour until Tully and Kate have a falling out. While Johnny at one point feels an attraction for Tully, it is never realized, but it becomes a source of jealousy for Kate throughout the book.

Since season 1 of the TV series ends on the cliffhanger that Tully has done something that Kate says she can never forgive her for, some viewers have speculated that Johnny and Tully have had an affair. However, Heigl told ET the two women's friendship would never be able to survive such a betrayal. "It cannot be that Tully sleeps with Johnny after they're married," she said. "I don't think any friendship comes back from that."

Tully never marries or miscarries in the Firefly Lane book

Tully is a career-driven woman in both the book and TV series, but in the novel, she has many romantic relationships yet never marries because she's too focused on succeeding as a journalist. Max (Jon-Michael Ecker) is a character created for the TV series and never appeared in the original source material. On the show, Max is an EMT and one of Tully's recurring love interests whom she meets at a bar. While he's deeply in love with her, she's too afraid to reciprocate and ends the relationship.

Max proposes when Tully learns she's pregnant, but she turns him down. Shockingly, Tully later changes her mind and proposes to him, and the unlikely couple elope, accompanied by Kate and Johnny, who officiates the ceremony. When Tully suffers a miscarriage, she drunkenly reveals to Max she regrets the marriage and is glad she miscarried, and even though she attempts a reconciliation, their marriage gets annulled.

Kate's parents have a different relationship on the show

Kate's parents — Margie and Bud — have a much more complicated relationship on the TV series than in the book. Margie was a faithful wife in the novel, but she has an affair on the Netflix series. In a flashback from the '70s, Tully's mother, Cloud, reveals during a holiday gathering that she saw Margie spending time with another man, which Margie denies. Other flashbacks show that Margie eventually becomes more open about her affair, seemingly speaking to her lover on the phone with her husband in the next room and inviting the other man into her home.

When Kate confronts her mother about the relationship, Margie tries to reassure Kate that she and Bud will never split because they still love each other. They no longer feel a puppy love, but a mature love, she says. In another flashback, Bud demands that Margie choose between him and the man she is having an affair with. She obviously picks Bud. Kate's parents are shown still together in old age in the show's modern timeline.

Book fans weren't expecting Bud's death on Firefly Lane

Throughout the Netflix series, a funeral is teased, leading up to the season 1 cliffhanger of Tully and Kate's falling out. Fans of the book were likely expecting a certain character's death at the end of the season and might have found themselves confused before realizing the show was deviating from the book in a big way. At first, Tully seems to be the recently departed, but she eventually shows up for the funeral, too.

While a significant character indeed dies at the end of the novel, Bud is still alive when the book version of Firefly Lane ends. However, on the TV show, it turns out the funeral is for Bud, Kate's father, who has died from an unexplained cause. It's probable he died from a heart attack. A flashback from the 1980s shows Kate abandoning a date because her father has had a heart attack. Regardless of the cause, his loss seems to have a large impact on Kate and Sean.