[1][2] From debut on the show, Whitney became known for often being involved in tragic storylines, including the fracturing of her family life; her sexual abuse by Bianca's fiancé Tony King (Chris Coghill); her sexual exploitation by local pimp Rob Grayson (Jody Latham); her one-night stand with Joey Branning (David Witts) in the midst of being engaged to her first fiancé Tyler Moon (Tony Discipline); her marriage with Lee Carter (Danny-Boy Hatchard) that ultimately breaks down as a result of his depression; Lee's infidelity with Abi Branning (Lorna Fitzgerald), which resulted in him passing chlamydia to Whitney and consequently led her to miscarry their unborn baby; her romantic crush on Lee's father Mick (Danny Dyer); her wedding to Callum Highway (Tony Clay) that ends in disaster after she learns that he is having a romantic affair with Ben Mitchell (Max Bowden); being stalked by Tony's vengeful son Leo King (Tom Wells), which soon culminates with Whitney stabbing and killing him in self-defence; accidentally running over her close friend Kat Slater (Jessie Wallace) and then fleeing the scene; being impregnated by Zack Hudson (James Farrar); discovering that her baby has Edwards syndrome and omphalocele, which ultimately leads to her deciding to terminate her pregnancy; and illegally fostering Britney Wainwright (Lola Campbell).

The inappropriate nature of Whitney's relationship with Tony resulted in over 200 complaints being made to the BBC and television regulatory body Ofcom by members of the public, and was described by the Daily Mirror's Beth Neil as "one of the darkest and most disturbing storylines EastEnders has ever attempted".

As Whitney settles herself in Walford with her family, they get reacquainted with Bianca's boyfriend Tony King (Chris Coghill) following his release from prison.

Whitney convinces Peter and his sister Lucy (Melissa Suffield) not to report the attack to the police, but Tony blames her for the incident and ends their affair.

When Johnny's elder brother, Lee Carter (Danny-Boy Hatchard), returns from serving in Afghanistan, Whitney takes an instant liking to him and they share a kiss.

Gray Atkins (Toby-Alexander Smith) offers to represent Whitney and she is questioned by police who are doubtful as to why she would have gone to the boat party if she had killed Leo in self-defence.

Whitney takes time to recover from her ordeal and an unexpected kiss with Kush on Valentine's Day 2021 leads to the pair beginning a relationship.

Their daughter is diagnosed with Edwards syndrome and they are told that she will not survive after birth- Zack and Whitney make the heartbreaking decision to end her pregnancy on 2 March 2023.

Zack and Whitney begin a legitimate relationship in their grief, plant a tree in the allotments in Peach's memory, and later decide to become foster parents.

Not long after, Whitney discovers that she is pregnant again and decides to keep this from her adoptive aunt Sonia Fowler (Natalie Cassidy) who is also trying for a baby but had not been unsuccessful.

Whitney gives birth to Dolly Dean-Hudson but at the hospital, Britney overhears Zack and Lauren talking about their one night stand.

Whitney then realises that she has wasted her whole life relying on a man and plans to make a fresh start from Walford as a single mum to Britney and Dolly.

Whitney bids a final farewell to Sonia, Stacey, Chelsea and Felix before she boards a bus with Britney and Dolly as they head to Wakefield to live with Ryan.

Considering the character's role in the wider context of the show as a whole, it was decided that Whitney would be involved in a sexual relationship with Bianca's partner Tony King.

BBC News described the plot as an ongoing "predatory paedophile storyline", noting that this was the first time this subject matter had been tackled by a UK soap opera.

[8] The storyline was conceived when EastEnders series consultant Simon Ashdown viewed a documentary about homelessness, featuring a mother and child at a bus stop with nowhere to go.

Ashdown questioned what might happen if a paedophile were to befriend the mother in order to grow closer to the child, and related the scenario to Bianca's return to the soap.

In the event, McGarty's parents merely requested that their daughter not be asked to publicise the role, and the actress began filming her first scenes on 14 January 2008.

"[7] Narducci for the NSPCC stated that importance was placed on making children viewing the show "feel comfortable about asking for help if they felt they needed it [and] for the wider community – to recognise the signs and let them know that they can do something about it.

[7] Coghill has explained that Tony began grooming Whitney as soon as he met Bianca, ingratiating himself so as to become the family's "hero figure" and "saviour".

If one person out there who's been abused saw [the legal system] go out of their way to make it easier on the victim – Whitney's evidence is given by video link – it will be worth it.

Gilly Green, Head of UK Grants at Comic Relief, said: "It is vital that we continue to alert young people to the dangers if we are to stop them being exploited and the opportunity to work with EastEnders will make a huge audience aware of this issue.

"[17] The storyline begins when Bianca is sent to prison and Whitney rejects her family, moving in with Janine and attempting to make money by stealing from The Queen Victoria, causing her to get sacked, working for Max, whom she tries to kiss as she has a crush on him, and pickpocketing.

When she is caught, Rob rescues her from the situation and offers her what McGarty called a "dream life", which Whitney thinks is her chance to move up in the world as she feels lonely and has no friends.

[18] McGarty told Inside Soap that she hoped the storyline would have a positive impact, saying that she had done some research herself before filming, meeting teenage girls who had been exploited and hearing their experiences.

[25] The Guardian's Aida Edemariam said of the beginning of the storyline: "what is most disturbing, watching [Tony and Whitney's] first scenes together, is not the sexuality of the situation per se, though that is uncomfortable – it's the subtle blackmail with which he keeps her in line.

"[32] However, in contrast to public and media dissent, the NSPCC's director of communications, John Grounds, praised the storyline for "helping to raise awareness of the hidden nature of sexual abuse",[4] deeming it to be "vital in persuading people to take action to stop it and encouraging children to speak out.

"[4] Episodes from Whitney's storyline were submitted to the Royal Television Society Programme Awards 2008 for a panel to judge in the category Soap and Continuing Drama.

Members of the judging panel described the submitted episodes as "the culmination of a particularly challenging and controversial storyline which the production team, writers and cast pulled off triumphantly.

[36] In 2020, Sara Wallis and Ian Hyland from The Daily Mirror placed Whitney 52nd on their ranked list of the best EastEnders characters of all time, calling her "Gobby" and writing that she "has been through it".