Daniel also shared a sweet photo of himself and Ana dressed to impress, both with a drink in hand - a sparkling engagement ring visible on Ana's finger.
"On Friday I asked my best friend to marry me (for real this time). Here’s to forever loving you ❤️," he captioned the post.
He also posted a selfie of himself and his wife-to-be, the latter flaunting her new bling to his Instagram Stories.
Ana also shared the happy news on her own Instagram page, simply captioning a photo of herself and Daniel and a video of the happy couple arriving at a surprise party following their engagement with: "19.02.21 ♥️".
Aussie celebs flooded Daniel's post with messages of congratulations.
"How bloody good.. congrats mate !" exclaimed former Bachelor star Matty J.
"Congratulations guys!! The best news xx," penned Rebecca Harding.
Daniel's former Big Brother housemates also shared their joy.
"OH MY GOSH!!!!! YES GUYS i knew it!! 💛💛 I’m so proud of you two," wrote Sarah McDougal.
"Congrats legend! Happy for you guys," remarked breakout star Kieran Davidson.
In a chat with WHO in July last year whilst Big Brother was airing, Daniel, who missed out on the win to Chad Hurst, hinted that he and Ana would soon be making it official.
The couple split in late 2019 but rekindled things while Daniel was in the house.
“I definitely know that she’s the one that I want to spend the rest of life with,” he said.
“I think first and foremost we get through the Big Brother experience together and once we’ve come out the end of that, then we’ll reassess. But for me, she’s definitely the one I want to be with forever.”