Bindi Irwin addresses rift with grandfather Bob in Father's Day post: 'It breaks my heart'

Bindi Irwin is celebrating the incredible father figures in her life this Father's Day. But the star of TV's Crikey! It's the Irwins also spoke of her estranged grandfather, who is not a presence in her life.

Irwin, 22, who welcomed her first child in March with husband Chandler Powell, took to social media to honor the men who have supported her along the way, including her late dad, Steve Irwin. The Crocodile Hunter star died in 2006 after being pierced in the chest by a stingray's barb.

"Appreciation post for the three most incredible fathers in my life," said Irwin in the post. "My dad, my husband and my father-in-law. My dad taught me the importance of strength when standing up for what I believe in and to have empathy for all living beings. My husband amazes me every day with his kind and steadfast heart; his love for our daughter is infinite. My father-in-law works tirelessly for his family and is always there with a word of encouragement. These extraordinary men inspire me and I love them so very much."

While Irwin was thrilled to share her Father's Day joy, it seems there's also some heartbreak behind the post. On Facebook, Irwin responded to a comment inquiring why her paternal grandfather Bob, the founder of the Australia Zoo and father of Steve, was not mentioned in the Father's Day celebration.

“I really wish that my entire family could spend time with Grace. Unfortunately my grandfather Bob has shown no interest in spending time with me or my family," Irwin responded in a now-deleted comment, according to the West Australian. “It breaks my heart.”

Video: Bindi Irwin gives birth to first child with husband Chandler Powell

Irwin continued, explaining that her family financially supports her grandfather by “sending him funds every week" and building him a home "to ensure his well-being." However, her grandfather has not met her daughter, Grace.

“I want Bob’s happiness in life," said Irwin. "I have struggled with this relationship my entire life and it brings me enormous pain. I have to choose to care for my own mental health now.”

Becoming a parent without her father's presence has been a challenging experience for Irwin. Back in April, she opened up about her daughter not being able to meet the late Crocodile Hunter star in a clip from her Discovery+ series.

“It’s hard knowing that she’ll never get to actually meet [my dad], and it’s devastating because I’ll never get to watch that connection,” Today reported at the time. “But I cannot wait to be able to tell beautiful Grace all of these stories about Dad, to be able to share with her what an amazing father he was."

Irwin continued, adding how "it’s gonna be really special for her to know him through us... to tell her about what an amazing man he was."

She continued, "It is really hard, it’s hard that he’s not here because out of everyone in the world he would’ve loved her the most. He would’ve loved her so much, but I think, in a way, he is still with us. His heart and soul lives on in all of us, so he’s never really gone.”

Despite her grief, Irwin is working hard to keep her father's memory going strong. After celebrating Grace's 1-month birthday back in April, Irwin took to Instagram to share a series of photos of her infant daughter wearing a traditional Australia Zoo uniform of khakis.

"To celebrate one month, our beautiful Grace Warrior received her first khakis and met the star tortoises here at Australia Zoo," she captioned the adorable post. "We’re so proud of our Wildlife Warrior princess. I know our darling girl is going to grow up caring for Mother Earth and all her animals."

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