Australian TV star Bindi Irwin is among the celebrities who paid tribute to significant paternal figures in their life this father's day.

In a heartwarming post, the zookeeper described her late dad Steve Irwin, husband Chandler Powell, and her father-in-law Chris as the "three most incredible fathers" in her life.

"These extraordinary men inspire me and I love them so very much." She wrote. (check out her full tribute below)

Following this, fans quickly noticed that her grandfather, Bob Irwin, seems to be out of the picture. When one fan asked why is Bob not included in the post, she replied with a heartbreaking response.

"Unfortunately my grandfather Bob has shown no interest in spending time with me or my family," she wrote (via 7News). Irwin also claims that her grandpa publicly states that he wants to spend time with her family, but she has been experiencing "psychological abuse" from him her entire life.

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Besides this, she details that Bob has been returning the gifts that she sent him even though her family has continued giving him financial support since 1992.

She also added that she had been ignored by her grandfather ever since she was a little girl.

"Preferring to spend time doing anything else rather than being with me. He has never said a single kind word to me personally. It breaks my heart but it is not healthy to engage in an abusive relationship." she added.

Instead of holding grudges as the situation had brought her "enormous pain", the TV star concluded her comments by stating that everyone needs to be kind to one another and take good care of every individual's mental health.

How does Bob's family feel about Bindy's public response?

Showbiz Reporter Peter Ford recently told "Sunrise" (via News.com.au) that he had spoken to Bob's wife, Judy, about the situation. (watch a segment of the interview below)

He stated that Bob's family was shocked by the comments, and they were not aware of what's happening as they have no social media accounts. The reporter claims he felt that the family was devastated by the news.

Bindi Irwin, who recently gave birth to her first child, is the daughter of the late environmentalist Steve Irwin who died in 2006 after a stingray pierced his chest in the Great Barrier Reef.

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