Teresa and her husband, Mark Webber, welcomed their new son, Forest Sage, on December 12 in Adelaide.
She broke the baby news with a family picture.
The 30-year-old actress also uploaded some photos over Christmas.
Palmer is known for sharing the intimidate details of her life as a mother on her blog, Your Zen Mama.
She revealed that she co-sleeps with Forest as she did with Bodhi, “Forest sleeps on his back next to me and I just roll over and breastfeed him when he wants to feed.”