A photo has been circulating social media showing Steph - who is believed to be pregnant - lying on her back in a Liverpool car park.
It's alleged one Twitter user admitted to the attack, but later deleted the post.
While Stephanie, 23, has not commented on the alleged incident, her mum reportedly posted to Twitter: "You lowlife for assaulting a pregnant woman #gettingchargedmate #witnesses. She had just been assaulted and was shocked and shaken and the lowlife who assaulted her took a photo."
Her mother's Twitter account is private but The Sun claims to have seen the messages.
But a source told The Sun: "He didn't push her... she wasn't assaulted, she was knocked whilst people were trying to calm her down..."
Police told Daily Mail they'd received no report on the alleged incident yet.
Reveal has contacted Steph's rep.
The alleged attack came just a week after Stephanie announced she was pregnant in a now-deleted Instagram post.
She has not referenced the baby news since, although she has favourited a few tweets about pregnancy, including one that read: "Unplanned doesn't mean unwanted or unloved."
Meanwhile, ex-boyfriend Jeremy McConnell, 25, has said: "Just to be clear, if what is circulating is true, I'll always be responsible for my actions and I explained to Steph I'll speak to her, and do everything for her, if she stops drinking and partying knowing she's "pregnant". I'm sick of tit for tat but I won't let anyone slander me. I haven't been ideal in the relationship whatsoever, I'm trying to move on peacefully, it's a shock to most, but a kid can't fix a broken relationship."
They met on CBB in January but have had a rocky relationship, splitting and reuniting on numerous occasions. Their most recent break up was at the start of May.
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