Soldier Jonjo, who was booted off of the show by mentor Louis Walsh last October, will feature on their new record In My Dreams.
The group, which consists of wives and girlfriends of military personal, beat X Factor winners Little Mix to the Christmas number one last year with their single Wherever You Are.
Speaking about joining the group for a special song, Jonjo said today: "What the Wives have achieved in giving support to military families is incredible. To be part of their journey is very special for me."
And in one last twist, the group's album will be going head to head with X Factor runner up Marcus Collins, who releases his debut record next month too.