The pair, who play on-screen brothers Heath and Brax, are going head-to-head in this year's 'Most Popular New Male Talent' category.
Ewing told TV Week that he and Peacocke have now upped the stakes by making a mystery agreement ahead of the ceremony on April 15.
"I won't say what the bet is - it's between brothers," he commented. "We'll tell people afterwards!"
Meanwhile, Peacocke revealed that he is delighted by the success that he and Ewing have enjoyed.
"Dan's done a really good job and is a popular fella, so he's done great things for the show," Peacocke said.
"It's pretty awesome [to be nominated]. For the first couple of months, I thought I'd lose my job. I was really nervous and didn't think I was doing a good job, so I never imagined I'd be going to the Logies."
Neighbours star James Mason, Winners and Losers actor Tom Wren and My Sri Lanka's Peter Kuruvita are also in the running for the 'New Male Talent' prize.
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