EASTENDERS fans were in shock after they realised Bianca's unlikely family connection to a fellow Walford character.
Patsy Palmer returned to the play the longtime character as part of the exit story-line of Whitney Dean (played by Shona McGarty).
On EastEnders, she discovered that Zack Hudson (James Farrar) cheated on Whitney.
Although she says she knew about Nancy, he accidentally admitted he had slept with Lauren Branning (Jacqueline Jossa).
Bianca then stormed out of the house so she could tell her daughter the truth about their relationship.
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It just so happened that Lauren was in the street outside so Bianca landed a huge slap across her face, before she also slapped Zack.
After the moment aired on screen, some fans couldn't help but note that Bianca and Lauren are related to each other.
The pair are cousins as Bianca's mother Carol Jackson (Lindsey Coulson) is the sister of Max Branning (Jake Wood), Lauren's father.
Viewers flocked to X - formerly known as Twitter as they remembered the family connection between the pair and were shocked how Bianca slapped her close relation.
One fan wrote: "Wait I just realised Bianca and Lauren are cousins as well, losing my mind."
"I just d****** that Bianca and Lauren are cousins. Max is Bianca's uncle ????," said another.
A third viewer stated: "I forgot Bianca is first cousins with both Lauren."
Meanwhile, a fourth user commented: "I d****** forgot that Bianca and Lauren are cousins #EastEnders."
"Wait I just realised Bianca and Lauren are cousins as well #Eastenders," exclaimed a fifth watcher.
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And a sixth added: "Not bianca slapping lauren, has she forgotten that laurens her actuall cousin #EastEnders."
This comes as Shona McGarty prepares to leave the London based soap after 16 years on the square.
The actress informed producers last summer that she wished to leave Walford, but she says she’s never wavered since.
She admitted: "It was a really difficult decision, because it’s all I’ve ever known. I pretty much grew up on the Square, so I feel like I’m leaving home.
"But I had to put on my big girl pants and be quite brave, because life is so short, and you feel that more and more as you get older."
She added: "There are other opportunities and areas of the industry I want to explore before I get too old! All things come to an end and this is the new chapter of my life.
"So although it was a big decision, once I’d made it, I was quite resolute that this was something I had to do."
