The former cricketer went on to wish his "gorgeous wife" the "happiest of Birthdays".
"You have embraced every bit of being 4️⃣0️⃣& I love that about you!😍 #bestyearstocome❤️
"We are so proud of you for everything you have done, encountered & created to always help, create smiles & make a positive impact on the World 🌎 around you.. Especially on International Woman’s Day!"
Cam finished the post by thanking Jules for being an "amazing" wife and mother.
"But more than anything best friend!" he added. "Happy Birthday we love you."
The sweet tribute was soon met with plenty of support from fellow famous faces.
The Bachelor's Tim Robards sent his birthday wishes, while Holly Kingston from a later Bachie season shared the love with four red heart emojis.
Personal trainer Lauren Hannaford, who celebrated her husband Red Wiggle Simon Pryce's birthday on the same day, also penned a sweet message.
"HAPPY BIRTHDAY!!! I hope your day is as gorgeous as you! 😍❤️🎉 xxxxx," she wrote.
Leading up to Jules 40th, the MAFS star spoke to Stellar about the milestone, revealing what she's "manifesting" in this upcoming chapter.
"For some time now, we’ve been manifesting a little girl, whom we named together all the way back in the final week of the Married At First Sight experiment," the podcaster told the publication.
"I hope to announce a pregnancy in 2022," she continued, before adding that she is "really busy" but is hoping "history repeats itself".
"The key is to make sure I feel relaxed and not make it the centre of my universe. I think that’s what led to falling pregnant in two months with Ollie."
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