The news was also seemingly confirmed by Lara's facialist, celebrity skin specialist Melanie Grant, who operates a salon in Sydney's Double Bay, as well as in Los Angeles.
Melanie, who includes Victoria Beckham among her celebrity clients, shared a photo of three hands on her Instagram account while promoting a luxury hand cream, and referred to her friend Lara has a "new mama" in the caption.
Melanie wrote: "My hands Protect, Care and Treat. Show me what your hands can do! I'm gifting these three new mamas, Nicole Warne, Nicole Trunfio and Lara Worthington The Hand Treatment, until I can see them in real life."
Lara and Sam are yet to officially confirm the news and the couple have not posted any updates about their new addition on Instagram.
Lara first revealed she was pregnant with her third child back in November.
"Yes I'm pregnant! I'm having a boy, early next year. It's my third boy and we're all very excited and very happy," she told Vogue Australia.
Lara, who is the founder of beauty brand The Base and also holds ambassador roles with luxury brands including Tiffany & Co and Louis Vuitton, says her main focus now is being a mother.
"My family brings me so much happiness that nothing else really matters – that's just my focus [in life]," she says of motherhood.
"I feel like that's why I'm here, to lead that legacy."
And she says Sam is a wonderful parenting partner.
"My husband is amazing. He's a fantastic father, fantastic husband and we're a really good team," she previously gushed.
"We've grown together and grown as a family and I think that's the most important thing. He's just so good with the kids, he does the night feeds and everything – he is seriously superhuman!"
This story was originally published on our sister site Now To Love. Read it in full here.