TV presenter and former Olympian Johanna Griggs has just become a grandmother, revealing the happy news on Instagram over the weekend.

“Meet our gorgeous grandson… he is beyond exquisite,” the 44-year-old wrote alongside a snap of her 21-year-old son Joe’s first baby.

Joe, is the Better Homes and Gardens presenter's youngest son with her former husband, actor Gary Sweet. He and his partner, Katie, are said to be "completely calm and over the moon" about their new arrival.

"Both families ecstatic with the safe arrival of this much loved little man," Johanna wrote, confirming the baby boy had yet to be named.

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The 1990 Commonwealth Games bronze medalist also remarked on how "incredible" it was to see her son welcome a son of his own.

"Beyond surreal. Can't begin to to describe how incredible it is to see my baby holding his baby. What a beautiful day," she shared.

Johanna also shared a series of snaps of her grandson's arrival, revealing to her near-40,000 followers she was "bursting with pride and emotion".

"What a divine gift into all of our lives he is," she shared.

"Congrats again to Katie and Joe for producing such a gorgeous little bundle of perfection...How lucky are we all?????"

Johanna was a young mum herself, welcoming her first baby in her early twenties. She first shared the news she was set to become a grandma with fans in November, posting a picture of her son's girlfriend's growing belly.

"Got to feel my grandson kick for the first time tonight. It was so awesome," she shared at the time.

Got to feel my grandson kick for the first time tonight. It was so awesome. Katie is looking so beautiful, and everyone is so excited. Bring on 2018...:) #katieandjb #firstgrandchild #wecantwaittomeetthelittleman #excitingtimes

A post shared by Johanna Griggs (@johgriggs7) on Nov 9, 2017 at 1:42am PST

After revealing the news her grandson had been born, fans were quick to share in the TV presenter's joy.

"Congrats being a grandma is beyond amazing," one fan wrote, while another added: "The next chapter begins for your beautiful family".

"It's an amazing overwhelming feeling of love and joy to be a grandparent...enjoy this wonderful time in your lives," shared another.

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