Some of Holly's well-known storylines including being in a relationship with Jason Roscoe (Alfie Browne-Sykes), taking legal highs and cannabis, being kidnapped by Trevor Royle (Greg Wood) and Ashley Davidson (Kierston Wareing), having an affair with Jason's twin brother Robbie Roscoe (Charlie Wernham), discovering Alfie Nightingale (Richard Linnell) was her half-brother, causing a car crash while intoxicated, which caused the death of Rachel Hardy (Jennifer Brooke), being raped by her boyfriend Nick Savage (Ben-Ryan Davies), and discovering that her half-brother Alfie suffered mental illness.
Holly is conceived during her mother Cindy Cunningham's (Stephanie Waring) 16th birthday. Cindy keeps her pregnancy a secret from her parents. Holly's father Lee Stanley (Nathan Valente) is killed in a road accident shortly before her birth. After Holly is born on Christmas Day, a terrified Cindy abandons her outside the hospital and desperately tries to carry on as normal. She returns home a few hours later and is told that her sister Dawn Cunningham (Lisa Williamson) has died of leukaemia. Cindy's parents, Gordon (Bernard Latham) and Angela Cunningham (Liz Stooke), find out about her secret pregnancy and force her into motherhood. Cindy struggles to adapt to life as a single mum and on one occasion, attempts to suffocate Holly, but her older sister, Jude (Davinia Taylor) stops her before any damage is done. The shock of the situation makes Cindy realise that she does genuinely love her baby.
When Cindy is forced to take Holly to work at The Loft with her, Holly falls safely asleep in the cloakroom, but later awakens and finds an ecstasy tablet, which she swallows. Holly is rushed to hospital and Cindy knows social services will take Holly out of her care, and so she concludes that she has no choice but to flee the country with her daughter. She takes Holly from hospital and they leave for the airport. Cindy and a four-year-old Holly return in May 2002. Cindy scams her brother Max Cunningham (Matt Littler) and Max's friend Sam "O.B." O'Brien (Darren Jeffries) out of their money. She and Holly then leave again. In 2004, Cindy and a six-year-old Holly return for Cindy's father Gordon and stepmother Helen Cunningham's (Kathryn George) funerals, along with her grandmother Angela.
In June 2008, Cindy and a ten-year-old Holly return from Spain for Max's wedding to Steph Dean (Carley Stenson). After the death of Max on his wedding day, Cindy and Holly decide to stay permanently in Hollyoaks. It is then revealed that prior to his death, Max left Holly £3,000 in his will, which can only be accessed after her eighteenth birthday, but left Cindy his treasured DVD collection, much to Cindy's annoyance. Cindy sends Holly to spy on Warren Fox (Jamie Lomas) after Louise Summers (Roxanne McKee) accuses her of having an affair with him.
On Holly's first day of school, Cindy forgets to pick her up, so Holly is taken in by a concerned Tony Hutchinson (Nick Pickard), but this angers Cindy as she assumes he is a paedophile after it becomes public knowledge that he slept with fifteen-year-old Theresa McQueen (Jorgie Porter), though Tony thought she was of age at the time. Cindy begins a relationship with Rhys Ashworth (Andrew Moss), but Rhys and Holly of ten argue. However, one day Holly apparently goes missing, although she is actually hiding from Rhys, who lures her out of hiding with an episode of University Challenge. Holly and Rhys end up striking a friendship, however, Cindy ends her relationship with him. Cindy's young half-brother and Holly's friend Tom Cunningham (Ellis Hollins) and Holly find out Mercedes Fisher (Jennifer Metcalfe) has been stealing food from Il Gnosh, which she begins selling for profit. The pair then expose her. Cindy begins to get close to Tony, who impresses both Cindy and Holly. Tony proposes to Cindy and the pair get married, after which, Holly, as well as Cindy, changes her surname to Hutchinson.
Holly is accidentally electrocuted at The Dog in the Pond by Darren Osborne's (Ashley Taylor Dawson) Christmas lights. Holly is not breathing, but Darren resuscitates her; he tells Cindy that she was resuscitated by Jake Dean (Kevin Sacre).
In February 2010, Cindy sees an advert for an under-twelves talent show and announces that Holly will be entering. Holly isn't all that keen but agrees to do it, thinking that it will get her more attention from her mum. Holly then realises that Cindy has her own selfish motives for wanting her to win and overhears Cindy tell Tony that the talent show isn't important. Holly tries to talk to Tony's half-brother Dominic Reilly (John Pickard), who is preparing a meal in the kitchen, about how Cindy is treating her, but this distracts Dom from his cooking - he drops his pan of food on the floor and shouts at Holly, causing her to run off, feeling even more isolated and alone.