The Strawberry Kisses singer made the surprise announcement on Sunrise on Friday morning.
The now 30-year-old, who is already a proud mother of daughter Skylah with husband Matthew McMah, called her son Malachi.
Speaking to weatherman Sam Mac on the popular morning show, Nikki said she is thrilled with the new addition to her family.
'I am super happy. I have my princess Skylah and Malachi,' she gushed.
'I am all for Nikki 2.0 - bring it on,' she told an Australian publication at the time.
This article originally appeared on New Idea