After an absence of nearly eight years, Manchester-born Tina returned to the cobbles as Sarah-Louise Platt in 2015.
Paula, who plays Tina’s on-screen sister-in-law Kylie Platt, is pregnant with her second child and will bow out of the ITV soap before her baby is born in the summer.
Tina O’Brien (Yui Mok/PA)
“Selfishly, I’m gutted,” Tina said. “I absolutely adore her. I think for her it’s the right thing to do. She’s ready to go and I completely understand her going, but me personally, I’m like ‘nooooo!’”
The 32-year-old added: “I really love working with her. She’s such a fantastic actress and she’s going to do great.”
Paula Lane (Dominic Lipinski/PA)
Among the first to welcome mum-of-two Tina back to the cobbles last year was Ryan Thomas.
The actor, who is also leaving Coronation Street this year, not only plays her character’s ex-husband Jason Grimshaw, he is also Tina’s former partner and the father of her daughter.
The Corrie favourite marked her return with a high-profile storyline which saw Sarah begin a doomed love affair with evil Callum Logan (Sean Ward).
Tina and Sean Ward filming last year (Joseph Scanlon/ITV/PA)
Kylie ended up killing the drug-dealing villain during Corrie’s live episode in 2015.
The Platts all conspired to hide the body by burying it under the foundations of their mother Gail McIntyre’s new annexe.
The live broadcast in September went without a hitch and Tina said she ‘loved every second of it’.
“It’s probably one of the things, when I’m older, I’ll bore everyone with,” she stated.
Tina in 2013 (Ian West/PA)
Asked to gauge Gail’s reaction when Logan’s corpse is eventually dug up, Tina said: “She’s just going to be devastated.”
The petite blonde added: “I mean, poor Gail. Even when something really lovely happens and she gets something really nice in her life… there’s been a body buried there the whole time.”
Shortly after Callum’s death, Sarah discovered she was pregnant with his baby. But the birth of son Harry last month was far from smooth sailing.
He was born five weeks early by Caesarean section to the single mum, who is yet to experience a pregnancy without incident.
Bethany’s birth in 2000 (Granada TV/PA)
In a storyline which shocked millions of viewers, Sarah became a teenage mum when she had daughter Bethany, currently played by Lucy Fallon, at the age of 13.
During her relationship with Todd Grimshaw (Bruno Langley), she became pregnant again, but the young mum suffered a placental abruption and had to have an emergency caesarean.
The baby boy, named Billy, died.
Harry is healthy, but his birth has sparked anxieties in Sarah and she will face a battle with post-natal depression.
“I think it’ll be the hardest thing I’ve ever played,” Tina said. “I’m so excited because it will really push me.”
BBC One soap EastEnders recently turned the spotlight on postpartum psychosis.
EastEnders’ Stacey (Lacey Turner) and Martin (James Bye) get closer (BBC)
Since the birth of baby son Arthur, Albert Square’s Stacey Branning (played by Lacey Turner) has struggled with the condition.
Symptoms can include hallucinations and extreme confusion.
When asked if Sarah is destined for the same diagnosis, Tina said there may be ‘similarities’.
“To be honest, I’ve watched one episode and I absolutely adore Lacey, she’s a wonderful actress.
“There’s probably going to be similarities because they’ve both had children and I think as things go on with Sarah, I can assume that there will be more. Her head starts playing tricks with her so maybe there will be delusions.”
Tina sympathises with Sarah’s predicament: “Obviously I don’t know what it’s like to have someone buried underneath Mum’s floor, but she’s gone through a lot and a lot of these things are getting to her.”