The mum of two, who has played Sonia Fowler since she was ten, will leave as part of the BBC One show’s 40th anniversary — a decision she made in the summer.

In her first interview, exclusively with The Sun on Sunday, she said: “I’m 42 this year, I just feel like it’s time to be brave.

“You don’t want to get to 70 and think, ‘I never tried that’.

“I’ve loved this programme with all my heart. I started at ten, it’s in my bones, it’s in my heart.”

Natalie made the decision following a heart-to-heart with the soap’s top boss Chris Clenshaw six months ago.

She said: “I’d been thinking about it for a little while. I had a wonderful chat with Chris back in the summer. It’s just exciting.”

Natalie will now film her final scenes later this month.

‘Iconic moment’

A week of anniversary episodes will see a huge explosion rip through the Queen Vic pub and rumours are rife that Natalie’s popular character could die in the blast.

But she’s staying tight-lipped about the fate of Sonia, who has recently been on trial wrongly accused of killing Debbie Colwell.

Natalie said: “I’ve got to remember in my head that when, as an actress, you make a decision to leave a show like this, you can’t hypothesise or worry about what’s going to happen to your character.

“That is down to the boss and the storyliners as the fate of Sonia is in their hands. I’ve had to take a deep breath, and go, ‘I’ve made my decision, I’ve just got to let it play out’.”

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Natalie arrived in Albert Square in 1993 as part of the rowdy Jackson clan, which included sister Bianca, played by Patsy Palmer; brother Robbie, portrayed by Dean Gaffney; and Lindsey Coulson as mum Carol. 

She left in 2007, before returning briefly between 2010 and 2011, and again in 2014.

Her earliest memory is being given a new bomber jacket that she had to “dirty up” at school to look worn.

She said: “I was like, ‘I absolutely love Sonia, she’s going to be a real tearaway’, and it never turned out like that.”

The show’s biggest stars across the decades, including June Brown, Pam St Clement, Barbara Windsor, Wendy Richard, Letitia Dean and Natalie’s on-screen mum Lindsey, all took her under their wing.

But it was her friendships with legendary actresses June, who played Dot Cotton, and Wendy as Pauline Fowler, that led to nights out and holidays.

I think the show relies on strong matriarchal women and I think that’s how this show works

Natalie Cassidy

She said: “I was going out with June, aged 18, having a glass of red wine with her in The Ivy when she was in her seventies.

“We went to Malta and we sat in a Jacuzzi together having a laugh. We stripped off!

“I used to go round to Wendy’s and we’d learn our lines in our pyjamas and have sleepovers! It was great. You made friendships that were just amazing.”

Natalie, who lives with her two daughters and cameraman fiancé Marc Humphreys, can’t remember a time in her life when fans didn’t say hello — even when she popped to the supermarket in her PJs.

She said: “The kids love it, it’s just part of my life. It’s not like it happened a couple of years in, so I’m very, very lucky that it’s been that way. I can’t remember not being recognised.

“The more local you get, they get used to seeing you. ‘Oh, it’s just Nat in her pyjamas again, running around getting her shopping’.”

Sonia, where’s your trumpet?

Natalie Cassidy

Natalie revealed she still loves it when people say, “Sonia, where’s your trumpet?” following a storyline involving her character learning to play the instrument in the Nineties.

She said: “I still get that, I still get it all the time.

“And do you know what? I get people saying, ‘Oh does that annoy you?’.

“How can it annoy me? It’s so wonderful to have an iconic moment. So no, I’m never annoyed when people say ‘Sonia, where’s your trumpet?’. I absolutely love it.”

Looking back on the last 32 years, and thinking about her stand-out storylines and plot twists, Natalie added: “It’s really funny, because there are obvious ones, like giving birth in my teens, or my boyfriend Jamie dying in hospital on Christmas Day, which were massive.

“But some of my favourites are filming a hen party round at Stacey Slater’s, where you’ve all got facemasks on, cucumbers on your eyes . . . all the women together.

“I think the show relies on strong matriarchal women and I think that’s how this show works.

“I’m proud of all of it.”