Robert Irwin and Heath Ledger's Niece Are Official

Robert Irwin and girlfriend Rorie Buckey have gone official on Instagram, earning Bindi Irwin's seal of approval.

Robert and Rorie (who is Heath Ledger's niece) shared their first pic together, a selfie showcasing the two on a sidewalk in front of a flowering tree and park. 

This was shared almost two months after the two made their public debut walking a red carpet together.

Bindi reposted the pic on her Story and said, "The sweetest. Love you both." Rorie shared the Story, saying, "Love you @bindisueirwin."

Rorie's image is different to Robert's. Hers shows the two together in front of a fence by a lake, captioning the post "Adventure buddy," with an added heart hands emoji. 

Robert commented a red heart emoji.

"You guys," Bindi commented, with three yellow heart emojis. Bindi's husband, Chandler Powell, liked the post.

Rorie's twin sister also expressed her support saying, "So much love for you both," adding an emoji of a smiling face with open hands.

Two weeks before, Rorie hinted at their romance, posting a collage of pics from her visit to the Steve Irwin Wildlife Reserve, including a pic of herself wearing the signature Australia Zoo khaki shirt. "Croc trip so far!!"

Rorie is the daughter of one of Heath's sisters, Kate. She and Robert made their debut on the red carpet for the premiere of 'Mission: Impossible - Dead Reckoning Part One' in Sydney. 

They first sparked romance rumours last November, after they were spotted together on a Queensland beach. The next month, for Robert's birthday, they were photographed sitting with Terri Irwin at Australia Zoo.

In December, her dad Nathan was quoted saying he "absolutely" approved of their relationship.