“Baby bump is getting bigger!” she captioned the sweet post.
“We’re getting close to the halfway point and I think our Australia Zoo animal family is excited to meet our daughter next year. Even Forest the giraffe is wondering what’s happening!”
Delighted fans rushed to the comments to share their happiness at the couple’s new photo.
“Awww this is the sweetest, what a beautiful family, giraffes included ♥” one person wrote, while another added, “They say animals can sense pregnancy. Our boy cat was very affectionate during my 2nd pregnancy.”
Just weeks ago, Bindi uploaded her first baby bump photo and shared an update in the caption.
“My beautiful mum [Terri Irwin] took this photo yesterday. Baby girl is doing great,” Bindi, who is the daughter of the late Crocodile Hunter Steve Irwin, wrote.
“Every time we get an ultrasound she’s incredibly energetic and always moving around. She’s now about the same size as a mountain pygmy-possum. Too cute!”
Bindi and Chandler, who married at Australia Zoo in March, first revealed news of Bindi’s pregnancy in August.
“Baby Wildlife Warrior due 2021," Bindi wrote on Instagram at the time.
"Chandler and I are proud to announce that we’re expecting! It’s an honour to share this special moment in our lives with you.
"Though I’m still in my first trimester, we really want you to be part of our journey from the beginning of this new life chapter.”
Bindi’s father Steve tragically died in 2006 after being attacked by a stingray while filming a wildlife documentary in Port Douglas, NSW. Bindi was just eight years old at the time.