Bindi Irwin Raves About Brother Robert's 'Gorgeous Girlfriend' Rorie Buckey in Sweet Family Tribute Post

Robert Irwin's girlfriend Rorie Buckey has his big sister's stamp of approval!.

In a sweet Instagram post shared Monday, Bindi Irwin professed her love for her younger brother's "gorgeous girlfriend" as she shared her gratitude for the people in her life.

Bindi, 25, first called her 19-year-old brother the “extrovert” of the Irwin family as she described him as “hilarious and definitely on a giant non-stop adventure in life," before praising his adventure partner.

“Sweetest soul, beautiful friend, I love her dearly,” Bindi wrote of Buckey, 19, who is the niece of the late Oscar winner Heath Ledger. In the selfie Bindi posted, Buckey posed with her arms around Robert and Bindi's mother, Terri Irwin.

She added that Buckey is also a favorite of her 2-year-old daughter. “You’ll usually see Grace just following her around because she adores her,” Bindi wrote in the post.

Speculation about Robert and Buckey's relationship has been circling since last November when they were photographed together in Australia.

In December, they were seen seen at the Australia Zoo together on Robert's birthday and in April at the airport in Perth.

They made their red carpet debut as a couple in July, posing together at the Australia premiere of Mission: Impossible — Dead Reckoning Part One.

The following month, the pair went Instagram-official with their relationship, with Robert posting a selfie of them on Aug. 24 and Buckey posting the next day and referring to him as her "adventure buddy."

Bindi’s Instagram lovefest didn’t end with her brother and his girlfriend, though. She also celebrated Terri, 59, whom she called the “matriarch of the family” and “the most thoughtful and giving heart.”

“Her endless knowledge, determination and unconditional love inspires me every day,” Bindi wrote.

Of her husband, Chandler Powell, Bindi wrote: “Strongest and kindest man I’ve ever known, always there for our family, best Dada to Grace, takes on any and every challenge and is up for each adventure life throws our way.”

The nature conservationist added that Grace is “a little whirlwind of beautiful energy.”

Bindi told PEOPLE for her August cover story that she and her husband, Powell, 26, consider their daughter a “tiny little miracle" due to her struggles with endometriosis. 

“There was every chance that we wouldn't have been able to have a little one, so to have our beautiful girl, we are so lucky,” she said as she reflected on her endometriosis journey. 

After spending years dealing with pain, fatigue and nausea and several unsuccessful attempts to diagnose her, she learned through a laparoscopy that she had the reproductive condition in which uterine tissue grows outside of the uterus, causing cramping and chronic pain.

“I was so scared that they wouldn’t find anything because we had run out of everything else to test for,” she recalled. “After years of doctors and various people telling you there’s nothing, you really start to believe it. You wind up in this strange space of self-doubt, fear and insecurity. That’s hard to overcome.”

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Now, she’s grateful for the time she gets to spend with her toddler.

“I wake up in the morning, and I don’t have to take anti-nausea medicine or have my heat pack. Being able to go for a walk with my daughter and not feeling like I have to throw up in the bushes is just wild to me,” she shared. 

“I feel like I have a second chance at life," she added. "I feel brand-new.”