Speaking on the Today show on Monday, Political Editor Chris Uhlmann said there was "growing discontent" in the National Party, with party elders believing Mr Joyce was doing irreparable brand damage.
Mr Drum's taxpayer-funded staffing allocation was reportedly boosted to accommodate Ms Campion.
All of these people should have been unable to employ Campion, according to the ministerial code of conduct, which says that ministers' "close relatives and partners are not to be appointed to positions in their ministerial or electorate offices and must not be employed in the offices of other members of the executive government without the Prime Minister's express approval".
Mr Turnbull said the Nationals were provided with a specific number of personal staff positions as a share of the government's overall staffing pool.
The spokesman said the deputy prime minister was still married when Ms Campion's appointments were made.
'I don't know, you don't know, the ins and outs of what arrangements have been struck.
Mr Joyce's relationship with the pregnant Ms Campion was publicly confirmed last week just two months after he told parliament his 24-year marriage was over.
The impact of Joyce's affair has had on those around him hit no-one harder than his now-ex wife, Natalie, and their daughters.
The government maintains nothing untoward happened, pointing to Ms Campion's strong jobs skills.
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He said , "Right now, I would say the Palestinians are not looking to make peace, they are not looking to make peace". Also in the interview, Trump criticized Israel's continued building of communities in Yehudah and Shomron.
The Australian have reported that this property was provided for free for a local businessman (and known friend of Mr Joyce) Greg Maguire.More as this story develops.
Mr Joyce moved out of his Tamworth family home in December and later moved into the townhouse he now shares with Ms Campion.
Questions are now being asked about Ms Campion's employment during her time with the federal Nationals, after the media advisor past year moved from Mr Joyce's office to the office of minister Matt Canavan and later to the office of Nationals whip Damian Drum.
But Foreign Minister Julie Bishop told media it would be "very difficult" to draft legislation that could cross so easily into people's private lives.
"The Prime Minister's Office has an administrative role in informing the Department of Finance of changes", Mr Joyce said.
Mr Canavan issued a statement claiming Ms Campion was "suitably qualified" for the role for which she was hired.
'Naturally we feel deceived and hurt by the actions of Barnaby and the staff member involved'.
Photos obtained by Daily Mail Australia show the pair looking happy together nearly a year before Mr Joyce's marriage break up and affair was revealed.