Quick to pen her support was fellow presenter Jessica Rowe.
"How wonderful. Lots of love ❤️❤️❤️" the former Today Show host wrote.
"Such a beautiful photo of you both Mel," another user added.
"Looking like her dad now xx," a third penned, referring to the radio host's husband, John Dunlop.
Just last year, Melissa spoke to 9Honey about preparing to be an 'HSC Mum' once again, after already supporting her son Nicholas through his exams.
"My daughter Talia is just about to turn 17 and is doing her HSC next year," she told the publication. "The moment when they get their license and they don't need you and they get in the car and those heart-in-mouth moments and then my son picks up my daughter and they are in a car together, it's one of those moments when you have to learn to let go."
The proud mum met her now-husband John when she was just 23. After initially rejecting his invite to take part in a celebrity swimming race in Canberra, the presenter agreed to make it up to him by going on a date.
The pair then tied the knot in 1995, before welcoming their first child, Nicholas, in 2001, and second, Natalia, in 2003.
Melissa spoke about her relationship with John to the Sydney Morning Herald back in 2014, saying she was "attracted to him in all sorts of ways".
“John is just a really nice, decent human being. He is also fantastic looking. I am attracted to him in all sorts of ways."
She went on to divulge the sweet gesture John used to perform while they were dating.
“He used to leave love notes. I'd find them on my car windscreen or hidden in my apartment. Early on, he also gave me a lovebird for his 'lovebird'."
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