According to OK! Online, a source close to Dani, 24, she had "suspicions" that "something was going on" while she and Jack were still reported to be an item.
A unidentified insider is reported to have claimed: "When Dani found out Jack was going to be a dad, she was a bit upset about it because she did the math.
"Dani knows who the baby's mother is and she had her suspicions while she was still with Jack that something was going on between them."
However, the source hinted she has already moved on.
They continued: "If anything, she's happy that Jack's happy and wishes him luck in the future."
Dani knows who the baby's mother is and she had her suspicions while she was still with Jack that something was going on between them.
ED! has approached a rep for Dani for comment.
This afternoon she broke her social media silence by posing for a glam selfie uploaded to her Instagram Stories before announcing she would be making a radio appearance.
When asked by Rylan Clark-Neal on his BBC Radio 2 show if she knew about the baby, Dani said: "No of course not! No news! When everyone else found out, I found out."
However, she offered her congratulations to Jack, saying: "Everyone loves a baby, congratulations!"
Earlier today Jack shared a cute picture of himself cuddling Blossom as he broke the news to his 2.2 million followers.
He told them: "This is undoubtedly the best thing that has ever happened to me, and it's true what they say, the instant feeling of love and connection you have with your child is a feeling like no other."
The stationary sales manager then revealed that he is no longer with Blossom's mum.
He continued: "I want to thank my family and friends for your continued support, also to my little girl's mother, who has been totally AMAZING throughout.
"Although we are not together, we are great friends, as we have been for many years, and our priority is co-parenting our beautiful baby girl. Both mum and baby are doing great."
Dani got together with Jack in the 2018 series of Love Island, and even received approval from her actor dad Danny Dyer.
The EastEnders star, 42, told her in a video call on the ITV show: "Babe, he's lovely. He's a proper geezer, mate. You've found a right proper geezer in there."
However, in April last year, Dani and Jack announced that they were going their separate ways.
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