"Jeez he's alright isn't he. Happy birthday Mills!!" former Bachelorette Georgia Love wrote in the comments.
"What a guy," Sunrise weatherman Sam Mac added, while Studio 10's Sarah Harris wrote: "Happy Birthday legend."
Georgie's tribute comes just six weeks after Rob shared an appreciation post of his own.
Posting a photo of his smiling fiancée rocking double denim, the former Neighbours star wrote: "When she's not working 2 Jobs, breaking down the issues of the day for everyone, she's jetsetting across the world to see her best friends…
"She's buying groceries for my covid iso, she's surprising me with congratulatory donuts, she's proof reading my writing, she's watching all of the footy with me, she's making time for herself, hitting the gym, she's living her best damn life, and she's doing it in double denim.
"She's the bloody best. So proud of you Tunny. See you tonight x."
Rob and Georgie's romance started in 2018, when the Australian Idol alum slid into the-then ABC sports presenter's DMs after being entranced by her beauty and articulateness on screen.
The move paid off as their love story blossomed, with Rob eventually popping the question in late 2021.
Four years after meeting, it's clear the Hairspray star is still as enamoured with Georgie as day one.
"I read somewhere once that if both people think that they're batting above their average, the relationship is in a good place," he previously told Now To Love.
"I think she's just a sensational human being. She's funny, a lot smarter than me, she inspires me with her work ethic and who she is as a human."
This story originally appeared on our sister site, Now To Love.
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