Steph's dad, Nick, who is a builder and glazier, helped the pair with their bathroom on Sunday night's episode, however, even with the help, they still came last.
Ash and Leah were left infuriated that Nick was on-site and had, to their knowledge, not been inducted or paid for the work he did.
The pair called a body corporate meeting, with Steph and Gian unaware the meeting was about them.
"I didn't realise I was breaking the rules," Steph said, adding they didn't have any advantage as they still came last, they just wanted to finish the room.
Ash told her it was "against the rules" and said if he saw it happen again, he'd "lose it".
"You can't have someone paid on site who isn't inducted. We just need to be reminded of the rules," Leah said.
Steph began tearing up as she said that she'd felt like people were talking about her and Gian behind their backs but didn't know why, adding they should have just spoken to her directly when it had happened rather than waiting to pull everyone out of work to have a body corporate meeting.
Leah claimed she had "no time" to speak to Steph and Gian, however, a clip of her gossiping about the pair was aired, proving she definitely had the time.
Kyle didn't see the issue in Steph's dad helping, arguing if his dad was on the site, there would be no way he could stop him from working, especially if they were at risk of not finishing their room.
"I've actually never heard the guy speak," Leah told the cameras. "And I don't want him to ever speak to me again."
Fans were quick to slam Ash and Leah for what was quickly labelled as "bullying behaviour" on social media, with one Twitter user writing, "There was no need to be so aggressive and accusatory—was just plain nasty."
"The Block seems to encourage and promote bullying this season, so wrong," another added.
"Once again more drama that could have been avoided if the producers questioned, and stopped, the father from even going on site," a third said. "But they just allow it to happen."
"Need to find the mute button on a couple of them," a fourth quipped. "Didn’t realise this was a drama series thought it was about the building."
"Wow. Ash and Leah are next level mean girls," another wrote on Instagram.
"Bullying and high school drama," someone else added. "Build a house, do your own thing, show respect to others…or keep quiet. It’s not that hard. Geez. Don’t want to watch if it’s a Leah and Ash show all season."
Many others said they would stop watching the show as it "appears to be encouraging bullying".
Some also shared their appreciation for Kyle for standing up to Leah, with one user writing, "I think I love Kyle!! Stick it to them Kyle!"
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