Bindi Irwin Pens Birthday Tribute to 'Amazing' Mom Terri: 'I Love You More Than I Could Possibly Describe'

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Bindi Irwin is honoring mom Terri ahead of her special day!

The Crikey! It's the Irwins star posted a birthday tribute to the Irwin matriarch on Tuesday, sharing a photo of the pair alongside brother Robert, husband Chandler Powell, and her 15-month-old daughter, Grace Warrior.

"Mum, I couldn't wait to wish you a HAPPY BIRTHDAY!" Bindi, 23, began her note. "So excited to celebrate your birthday tomorrow and the amazing, beautiful, inspiring person you are. Thank you for being born. ❤️"

RELATED: Bindi Irwin and Chandler Powell Explore Lighthouse with Baby Grace — and Grandma Terri Tags Along!

"I love you more than I could possibly describe and every day I'm grateful for your kind heart and strong soul," she continued. "Of all the good things in this world, you're the most wonderful."

Meanwhile, Bindi's brother Robert, 18, also shared a celebratory post of his own to commemorate the occasion. Terri turns 58 on Wednesday, July 20.

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"Happy birthday mum!" he wrote. "Thank you for taking us all on so many adventures and for inspiring me every single day,. You are the strongest person I know. Love you 💛"

Bindi's husband Chandler, 25, also marked Terri's birthday with a video of the two "releasing sea turtles to the EAC [East Australian Current]."

"Happy Birthday, Terri," he wrote in the caption. "Thank you for your unending kindness and constant support. Your unwavering strength and leadership inspires us all. Can't wait to party today!"

RELATED: Bindi Irwin Pays Tribute to Mother Terri for Mother's Day: 'Strongest, Most Loving and Caring Woman'

In May, Bindi opened up to PEOPLE about how becoming a mom made her see Terri in a new light.

"I probably tell my mom how much I appreciate everything she did on an hourly basis. Dad passed away when we were very little," she said at the time. "She is such a strong person, and she had to raise me and Robert mostly on her own."

Bindi added, "I cannot even begin to tell you the amount of respect and pride and gratefulness I have for my mom."

RELATED VIDEO: Robert Irwin Celebrated by Family and Friends on His 18th Birthday: 'Feels Very Surreal'

After her father, Crocodile Hunter star Steve Irwin, rose to international fame on his wildlife documentary television series, he was diving with stingrays for an underwater film titled Ocean's Deadliest when he died on Sept. 4, 2006, at age 44. Bindi was just 8 years old, while Robert was only 2.

"[Mom] managed to raise two little kids as well as taking care of Australia Zoo and making sure it kept running, making sure Dad's legacy continued on, keeping up with all of our conservation work on a global scale," continued Bindi. "I am speechless. I don't know how she did it all. She's such a strong superwoman."