Their pregnancy announcement was met with an influx of congratulatory messages from the pair's former BIP co-stars.
"AHHHHHHH!!!! SO BLOODY HAPPY FOR YOU GUYS!" Alisha Aitken-Radburn wrote.
Jessica Brody added, "IM SO HAPPY 😭😭," while Renee Barrett echoed, "Heart is so happy! Congratulations you beautiful people! ❤️❤️❤️❤️❤️❤️."
Mary and Conor were an unlikely match on this year's season of Bachelor In Paradise, with the pair forming a relationship that captured hearts around Australia.
Conor entered the island as a "cleanskin", having not previously appeared on a Bachelor franchise previously, while Mary had previously appeared on Matt Agnew's season.
After proclaiming their love at the finale, the couple revealed Mary and her daughter had moved to Tasmania to live with Conor.
A huge congratulations!