Steffy and her twin sister Phoebe (MacKenzie Mauzy) were born onscreen as the daughters of supercouple Ridge Forrester (Ronn Moss, later Thorsten Kaye) and Taylor Hayes (Hunter Tylo, later Krista Allen and Rebecca Budig) during the episode airing on September 21, 1999.

Wood's performance in the role has been met with favorable reception from audiences and critics, having garnered her two consecutive nominations for the Daytime Emmy Award for Outstanding Younger Actress in a Drama Series in 2012 and 2013.

[13] Last appearing on the credits in February 2014, it was confirmed in October 2014 that she would not be returning on a more permanent basis, stating: "Unfortunately we weren't on the same page contractually/scheduling etc (...) These things happen in this industry and I hope all my fans can understand that.

"[21] It was announced that on September 10, 2020, that Tanner Novlan's wife Kayla Ewell, who had previously portrayed Caitlin Ramirez on the show, would return to play an intimacy double or a stand-in for Wood as a result of the onset protocols due to the COVID-19 pandemic in the United States.

"[20] Jamey Giddens of the soap opera website Daytime Confidential characterized Steffy as "bitch-nasty",[24] while Wood has described her as strong-willed[25] and a vixen.

[31] Explaining her reaction to Steffy killing her cousin Alexandria Forrester (Ashlyn Pearce) in self-defense, Wood stated in August 2015: "When I first heard about it, I was in major shock, of course.

It was about the honesty and it was raw, and we could open up to each other in the heat of the moment"[25] A big storyline occurred for the character in 2008, when Phoebe is killed after the car her boyfriend Rick Forrester (Kyle Lowder) was driving crashes.

[37] Just before discovering Steffy is carrying his child, Liam nearly marries Hope in a "room service elopement" scheme arranged by Brooke; an ambush that was described as "evil" by Daytime Confidential.

Unaware that Steffy was developing a dependency on her opioids medication, Finn began to make frequent visits to her home after her stay at the hospital and provided her with some psychological counselling and friendship.

However, due to the fact that throughout the numerous visits, he began developing a profound attraction to Steffy, Finn expresses that it would be best that he remove himself as her doctor to maintain his integrity, professionalism and ethics.

Bell discloses that "it's fertile ground for the building of a new romance" as Finn becomes Steffy's confidant and helper as she deals with both her physical and emotional burdens and addiction to her opioids.

[45][46] Prior to their nuptials, Steffy meets Finn's adoptive parents, Jack (Ted King) and Li Finnegan (Naomi Matsuda).

[50] Steffy shows immense support to her husband, as Finn struggles to come to terms with his father's deception, bonding the two deeper in their marriage.

"[53] It was later revealed in late May that Finn had survived the shooting and was being nursed back to health by his mother Li, which signified that Novlan had never in fact exited the role.

Wood describes the reunion as "romantic, [...] passionate and raw" and emphasizes that Steffy feels "utterly on top of the world" as "her true love has literally come back to life.

In February 2001, a family trip to Saint Thomas—where Ridge and Taylor renew their vows—ends in devastation when two-year-old Steffy supposedly falls overboard during a storm and is presumed dead.

After another short visit to Los Angeles in February 2015, Steffy returns months later to help Ridge take over Forrester Creations by overthrowing Rick.

Steffy invites her mother, Taylor, to move in with her despite Hope's wishes for her to leave town after finding out she allegedly shot Bill Spencer.

In July 2020, after a motorbike accident, Steffy lands at the hospital and meets her doctor, John Finnegan (Tanner Novlan) and both experience an immediate attraction to each other and cultivate a love at first sight connection.

Months later, Steffy finds herself pregnant after she had a drunken stupor led to a one-night stand with Liam, leaving her questioning her child's paternity.

[59][60] On-Air On-Soaps said Wood had the "unique challenge" of making the despised character into a more complex and well-rounded one, who fans were rooting for, while also praising her as "one of the hardest working younger actresses in daytime today".

[62] While criticizing the material written for the character as being "often repetitive and silly", Sara Bibel of Xfinity opined in June 2012 that Wood is a "charismatic actress" who rises above the script to "deliver consistently interesting performances".

[20] In 2022, Charlie Mason from Soaps She Knows placed Steffy 5th on his ranked list of The Bold and the Beautiful's Best of the Best Characters Ever, commenting "The term "red-hot mama" was all but coined for Jacqueline MacInnes Wood's fierce and feisty alter ego, a cool rider with an exterior that's as tough as leather and a heart that — despite how Liam treats it!

[73] Steffy's romance with newcomer Finn earned positive acclaim from critics, who praised their chemistry both during social distancing protocols as well as post restrictions.

"[75] Charlene Bazarian highly emphasize that "Finn is the first man" in a very long time "who has captured Steffy's heart and fans of [the show] are excited to see what's in the future for this couple.

The reunion earned Soap Opera Digest's "Editor's Choice" in their August 29, 2022 issue, depicting it as a "perfect, precious, poignant moment, all was well in the B&B world, and in the 'Sinn' fandom.

"[85] Shay McBryde of ShowSnob.com, a site under the FanSided network, curated a "Best Soap Opera couples of 2023: The most sizzling romances on Daytime Television" list, where Steffy and Finn secured the fourth rank.

Highlighting their dynamic, Fairman writes, "Who doesn’t love the man of your dreams rescuing you from a deranged young woman who locked you up in a cage!

saw Wood rank ahead of fellow daytime actresses Hunter King (The Young and the Restless), Kristen Alderson and Lindsey Morgan (General Hospital), with readers favoring her as the likely winner of the award.

"[102] For the 2018 Daytime Emmy Awards, Wood received a nomination for Outstanding Supporting Actress in a Drama Series, yet lost her bid to Camryn Grimes from The Young and the Restless.