The cast and crew worked with child protection charity NSPCC on the storyline, while Mulkerrin met with abuse survivors during her research.

During the storyline Cleo is also involved in a car crash stunt, and takes the blame for killing Rachel Hardy (Jennifer Brooke) to protect her friend Holly Cunningham (Amanda Clapham).

The relationship has faced several obstacles, including a motorbike crash, Joel's recommitment to the Church, a kidnapping, and pregnancy.

[1] The show's executive producer Bryan Kirkwood stated, "Towards the end of this year we're going to meet an extended branch of the McQueen family.

Kilkelly's colleague, Sophie Dainty reported that Porsche and Celine would eventually be joined by their younger sister, but casting details had not been confirmed at the time.

[3] On 1 January 2015, Kilkelly announced that actress Nadine Rose Mulkerrin had been cast in the role of Porsche and Celine's sister, Cleo McQueen.

[10] A writer for the official Hollyoaks website commented that Cleo slowly gets used to living in a house full of "alpha females" and branded her "a drama-free McQueen".

[11] An Inside Soap columnist reported that Cleo's introduction would give viewers an insight into Porsche and Celine's backstory and their lives before they moved to the village.

[9] Mulkerrin explained that Cleo is "really clever" and was away on a scholarship, so when she spots Dylan Jenkins (James Fletcher) and Nico Blake (Persephone Swales-Dawson) spray painting a school wall, she points out that they have missed out an apostrophe and adds it in.

[14] When his friend Zack Loveday (Duayne Boachie) mentions that John Paul has been showing extra attention to him, Harry kisses Cleo in front of their classmates to prove his interest in her.

Her stepfather Pete Buchanan (Kai Owen) sees her with Harry and reports her to Jack Osborne (Jimmy McKenna) for unprofessional behaviour.

[20] On 12 June 2015, Kilkelly (Digital Spy) reported that as part of the show's long-running, issue-led storyline focusing on sexual abuse within the McQueen family, Cleo's stepfather Pete Buchanan (Owen) would form "an inappropriate relationship" with her.

The cast and crew worked with child protection charity NSPCC on the storyline and led a campaign titled "No More Secrets", which encourages victims to speak out.

Pete then reunites with their mother Reenie McQueen (Zöe Lucker) and acts as a stepfather to her daughters, which allows him to start manipulating Cleo.

She threatens to reveal their relationship and stop the wedding, so Pete tries to talk her round in an alleyway, but they are seen by Cleo's former boyfriend Harry Thompson.

[26] After receiving good test results, Cleo reconsiders her plan to run away with Pete and asks if they can wait until she has sat her A levels.

[27] While she is attending school for the last time, Holly Cunningham (Amanda Clapham) discovers Cleo's passport and travel tickets.

When he receives an anonymous message inviting him to an event at the Loft, he assumes it is from Cleo and is surprised when Lisa Loveday (Rachel Adedeji) makes advances towards him.

But when she catches him stealing money from Carmina McQueen's (Harlow Jones) christening cards, she feels guilty and confesses to her family that she has taken heroin.

[58] Mulkerrin admitted to being "really excited" about the storyline, as she had previously played a young mother in Waterloo Road and enjoyed working with babies.

[59] Cleo's bulimia battle comes to a head during her wedding to Joel, which occurs in a special episode airing on World Mental Health Day.

[60] Cleo has developed a "skewed and idealistic view on events", so while she thinks the day went well, in reality she woke up full of "self-loathing", had a run, purged after eating a bacon sandwich, covered up her numerous injuries, and had to pin her wedding dress to fit.

On 21 May 2024, it was revealed the Hollyoaks production team had made a deal with Home Office to "join forces" to produce a coercive control storyline involving Abe and Cleo.

[63] Home Office had previously worked with Hollyoaks to produce Maxine Minniver (Nikki Sanderson)'s abuse from an incel group led by Eric Foster (Angus Castle-Doughty).

[64] It was reported the soap's partnership with Home Office will "shine a light" on the harmful behaviours that can occur within controlling relationships and demonstrate the impact of violence on victims.

[63] Home Secretary James Cleverly, reacting to the upcoming plot, said: "Tackling violence against women and girls is a real priority for me.

By partnering with Hollyoaks, we're raising awareness of how to recognise these behaviours as well as empowering the public to call out abuse when they see it and safely intervene when appropriate.

He highlighted Cleo's attempt to stop Reenie from drinking as "an outstanding scene" and said "We've always been a fan of Zoe Lucker, but young Nadine Mulkerrin gives her a run for her money.

[75] The following year, another contributor to Inside Soap praised Mulkerrin and Nicole Barber-Lane for their performances during Pete's trial, saying "They share a powerful scene where Cleo finally realises the truth.

"[79] Sophie Dainty of Digital Spy pointed out that Cleo has experienced "her fair share of turmoil" since joining the soap and described her sexual abuse storyline as "harrowing".