Fans were quick to congratulate the Survivor star and her model wife on their little bundle of joy.
"She is absolutely perfect so so so happy for you both - gigantic virtual hug," one commented.
"Congratulations and welcome Svea. Such wonderful news," a second penned.
"I am so happy for you, Mo and Vinny. Congratulations!!! We needed this happiness in 2020," remarked a third.
Moana first announced the arrival of their child via an Instagram post on Tuesday evening.
"My heart is full ❤️ @isabellasofiacarlstrom," she captioned a close-up photo of Svea's tiny hand.
Shortly before, the AFLW player revealed that Isabella had gone into labour with a series of intimate images featuring Isabella and their beloved pet pooch.
"You know what this means..." she hinted in the caption.
Moana and Isabella announced their exciting pregnancy news back in May, telling fans that it was "a dream come true."
"We are going to be MUMS," a delighted Moana captioned a trio of images featuring the couple and their ultrasound picture.
"I don’t yet have the words to fully explain how happy we are. It’s a dream come true for us and in November we get to meet our little person."
"From the bottom of my heart, I want to thank @monashivf and the team for everything you have done to support us. You have helped make this dream a reality. Holding this in for 13 weeks has been so bloody hard. My heart is exploding."
The new mums also celebrated their first wedding anniversary in August.
"I can’t believe it been a year already, it feels like it was yesterday! What a year it’s been. We could never have imagined the world look like this a year ago," Isabella penned on Instagram at the time.
"In saying that it has still be the best year of my life because it was my first year being your Wife. You make me so happy and I love every single part of our life together. Standing stronger than ever bring on the next 100 years together. I love you @moanahope Happy happy Anniversary."