The pair, who have been married since 2007, are now proud parents of a baby boy, named Charlie Kingston.
Heynatz announced the news on Instagram along with a photo of their newborn’s tiny little foot.
She captioned the image with, "Thrilled to share the great news that we welcomed our beautiful little boy Charlie Kingston on Monday afternoon. We have been in a state of complete & absolute joy since. He's nothing short of spectacular!"
She added the hashtag 'proud parents'.
Heynatz announced her pregnancy in June, taking to social media to say she was, “bursting with excitement”.
Speaking to The Motherish previously about her body during pregnancy, Heynatz said, "There's definitely some awkward moments physically speaking but interestingly I feel like I've had a greater sense of body confidence, being pregnant. I don't think I was prepared at how much I would marvel at how incredible the human body is."
On becoming a mum, Erika added, "I'm really excited about meeting this little soul who's going to teach me my life's greatest lessons. And also show me the greatest breadth and depth of love. Creating a family is the most wonderful thing I can imagine."
Congratulations Erika and Andrew!
WATCH Erika Heynatz on Home and Away...