Mr Chester will be veterans affairs minister and Mr Pitt will be assistant minister to the deputy prime minister.
The politician also said she felt that Mr Joyce was attempting to bring he National Party down with him.
'It is causing them more and more damage all the time'.
"The matters that are in the papers today relating to Barnaby and Ms Campion are matters for them to resolve and I don't have any comments to make on it at all", he told reporters in western Sydney on Sunday.
Mr Joyce said he did not intend to get a paternity test and would raise Ms Campion's child as his own.
The Daily Telegraph reports Mr Joyce declined to participate in an interview prior to the story's publication.
"It's mine, on the record, there it is", Mr Joyce told Fairfax Media days ago.
At the same time Ms Campion was in far north Queensland.
"Anything that's personal in nature is nobody else's business but mine and Vikki's".
It has been a tumultuous month for the new couple, with news of their relationship splashed across front pages around the country and sparking a feud with Prime Minister Malcolm Turnbull, who responded with a ban on sexual relations between ministers and their staff.
The mixed messaging is unlikely to sit well with Joyce's political peers, who have not exactly taken kindly to his handling of the revelation and his seemingly callous treatment of Campion in order to save face.
Mt Joyce has expressed concern that the new baby boy would be subject to unfair scrutiny throughout his life, thanks to the circumstances surrounding his conception and upcoming birth.