It was just days after Jack became a dad to newborn Blossom, whose mother Casey Ranger is his long-time friend since he was a teenager.
Jack and Extra Camp star Emily were reportedly huddled up together and whispering in each other’s ears.
They were giggling and at one point looked as if they were sharing a cheeky snog – according to The Sun.
One onlooker said: “After kissing, Jack told her, ‘We can’t be seen together’ and they quickly went off elsewhere.”
Another added: “They’d retreated into a corner by some stairs in a bid not to be spotted but couldn’t keep their hands off each other.
“Jack kept pulling her closer and was touching the back of her neck. They seemed to want to keep it discreet as they left separately.”
MirrorOnline has reached out to representatives for Emily and Jack for comment.
Emily has been single since splitting with film producer Rob Jowers last September after six months together.
He said their “whirlwind” romance didn’t work out, but that they co parented well together because they have known each other so long.
“Because we’ve known each other a long time it just works,” he said.
“We’ve known each other for years, since I was 17.”
Jack, who threw himself into a party boy lifestyle after winning Love Island, also vowed to tone down on his wild side now he has greater responsibilities.
“I’m not going to be thinking about just myself anymore. It’s no longer just Jack now I’m thinking about my daughter and how I can make her future better.
“I never thought I’d ever think like that way but now I am and I couldn’t ask for anything better.”
The pair were recently spotted for the first time taking Blossom out in the car alongside Casey.
Jack took care of the tiny one – who wrapped up in a snuggly blanket – as he carried her in her car seat out of the car and inside.
Casey did not look like she has been suffering from sleepless nights as she radiated a happy glow.
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