Densy recalled the incident as she appeared on 'This Morning' on Tuesday (3 May) to discuss her stint as the newest member of the Slater clan.
She told hosts Holly Willoughby and Phillip Schofield: "I was sat in make-up, and of course, my hair is darker, which I did do for this role because I quite fancied a change. And I thought rather than have a wig on, it was a bit of a different thing.
"I heard ,when I was in make-up [puts on London accent], ‘Who’s that boy? Who’s that young boy?’. So of course I turned around, and was like ‘Don’t look now!’"
Denise will be seen popping up in tonight's episode, as her character arrives in Walford to see Kyle (Riley Carter-Millington), having being called by his worried sister, Stacey Branning (Lacey Turner).
It will be a particularly emotional reunion for mother and son, as it is the first time the two will have met since he began living his life as a man.
Despite only appearing in one episode, Denise - who appeared in rival soap ‘Coronation Street‘ from 1997 to 2000 as Rovers Return landlady Natalie Horrocks - admitted the character could pop up again in the future.
Asked about the possibility of a return, she said: "I never say never. I said I would never do 'Dancing On Ice'... 'and would you welcome onto the ice, Denise Welch and her skating partner Matt Evers'. I said, 'I'll never do Celebrity Big Brother'... 'And last into the house, Denise Welch!'"
"It was a lovely show, and if Kyle stays, there's always an opportunity for his mum to come back. And if they ask you, you're flattered and you work how that pans out," she added.
Denise's episode of 'EastEnders' airs tonight at 7.30pm on BBC One.
'This Morning' airs weekdays at 10.30am on ITV.
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