Robert took to the picture sharing platform on Thursday to share a selfie where he can be seen with an arm around Rorie as they both smile at the camera.
He captioned the shot with three flower emojis which appeared to be a reference to the flowered covered greenery that they were standing in front of.
Whispers of a romance between the 19-year-olds first emerged last November when they were first pictured together on a beach in Queensland.
Then, on Robert’s birthday in December, they were spotting sitting with his mother Terri Irwin at their family’s famous Australia Zoo.
Last month, they posed on the red carpet together at the Mission Impossible: Deadman’s Reckoning premiere in Sydney, Australia.
Both Robert and Rorie lost someone very special to them at a young age. Robert’s dad Steve, known as “The Crocodile Hunter”, was an Australian zookeeper and conservationist. He passed away September 4, 2006, reportedly due to a stingray attack at Batt Reef, Australia.
Rorie meanwhile is the daughter of Dark Knight actor Ledger’s sister Kate Ledger. The Oscar-winning star died on January 22, 2008, in his New York apartment reportedly from a accidental drug overdose at the age of 28.