She first appears on August 17, 2009 when Stephanie takes her and her sisters, Annabelle and Molly, to The Queen Victoria public house in Walford to warn Ronnie Mitchell to stay away from Joel. Joel eventually leaves Stephanie for Ronnie and moves into the pub.
On September 11, 2009, Hannah is seen when she goes for a picnic with her father in the park and on Joel's birthday on September 29, 2011, when it is revealed that it is Hannah's 10th birthday as well.
Hannah dislikes Ronnie, saying she stole her father from her, and Ronnie tells Hannah about Danielle, becoming increasingly upset as she does so, which scares Hannah. Joel returns to his family after Ronnie rejects him.
Seven years later, after Joel and Stephanie are killed in a boating accident, whilst on holiday, Hannah turns up on Ronnie's doorstep and accuses her of killing her parents.
Hannah reveals that Stephanie had only recently forgiven Joel for his affair with Ronnie, they had renewed their marriage vows and were on honeymoon when they died. Ronnie attempts to apologise, but Hannah is not convinced and tells Ronnie that she and her sisters are now living with their uncle, Joel's brother, Tim Reynolds. Hannah also tells Ronnie that she wants to leave school and get a job to take care of her sisters, before leaving.
Ronnie later meets Hannah and Tim and gives Tim a cheque to help look after Joel's daughters. Hannah tears up the cheque and tells Ronnie that she does not want any "blood money" from her and tells her that her father had been right about Ronnie being "dead inside". She and Tim then leave.
When Ronnie realises she is being stalked, she suspects Hannah and calls Tim, who brings Hannah to see her. Hannah denies being the stalker, and she and Ronnie bond over their memories of Joel. Ronnie offers support at any time, but Jack Branning discovers that Hannah sent Ronnie flowers in Danielle's name with a message saying "RIP", and when Ronnie tells Hannah she knows this. Hannah, who is holding Ronnie's son Matthew Mitchell-Cotton, steps into the road into the path of a car.
They are saved by Andy Flynn and Hannah is arrested for harassing Ronnie. Hannah goes missing before her court appearance, and after she is found, Ronnie decides to speak in her defence in court.
Afterwards, Hannah and Tim tell Ronnie that the charges against Hannah have been dropped. Hannah insists that she did not send Ronnie any death threats. She and Tim then leave. It is later revealed that Andy, Danielle's adopted brother, is the stalker and had framed Hannah.