Katherine Schwarzenegger Posts Childhood Pics in Birthday Tribute to Dad Arnold: 'We Love You!'

Arnold Schwarzenegger; Katherine Schwarzenegger
Arnold Schwarzenegger; Katherine Schwarzenegger

Katherine Schwarzenegger Instagram

Katherine Schwarzenegger is celebrating her father Arnold's 75th birthday!

In an Instagram post on Saturday, the mom of two, 32, celebrated The Terminator star's big day with a series of childhood photos.

In the first, the duo is riding horses as Arnold jokes around with a peace sign behind her head. This is followed by pics of a young Katherine climbing her dad's arms in the pool and one of Katherine and sister Christina being all smiles as their dad holds them in the air.

Arnold Schwarzenegger; Katherine Schwarzenegger
Arnold Schwarzenegger; Katherine Schwarzenegger

Katherine Schwarzenegger Instagram

In the last picture in the gallery, a more recent one, Arnold is shown carrying Katherine and husband Chris Pratt's one-year-old daughter Lyla Maria.

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"Happy birthday daddy!! We love you so much!" Katherine wrote in the post caption. "You're the best and most fun opa and dad and we are all so lucky to have you in our lives! Happy happy!!"

RELATED: Katherine Schwarzenegger Shares First Photos of Baby Eloise, Honors Chris Pratt on Father's Day

While appearing on Jimmy Kimmel Live! in February, The 6th Day actor gushed about his growing family.

"It's the easiest thing to be a grandfather," said Schwarzenegger. "They come over to the house, you play with Lyla for around an hour or two, put her on the horse, put her with the dog. And after two hours, they leave," he joked, clapping his hands in front of host Jimmy Kimmel.

"It's fantastic! I have a great time when they come over to the house."

Speaking about his son-in-law, the former governor of California called Pratt, 42, a "fantastic guy" and "a great son-in-law." Sharing similar praise for his author daughter he continued, "I love my daughter. Katherine is so wonderful and I'm so proud of her."

"When they come over the whole house lights up," he added.

On Saturday, Pratt returned the love, posting "Happy birthday to the man, the myth, and the legend. Love you @schwarzenegger!" on Instagram alongside a picture of the pair sharing a couple of large cigars.

Schwarzenegger's son Patrick, 28, also joined in on the fun, posting an image of his dad cutting his head with a pair of large kitchen scissors alongside the caption "What can't you do? Love you ArnOLD. 75. Damn. HAPPY BIRTHDAY."

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Last month, it was Pratt's turn for celebrations as he turned 43 and received an Instagram birthday tribute of his own.

"Birthday Boy!" Katherine wrote in her caption. "Happy birthday to you! We love you so much! I feel like the luckiest in the world to live life with you."

Katherine went on to sing Pratt's praises. "You're the most loving father, the most supportive partner and you have the biggest heart and we are so blessed to feel and witness your love," she added. "Happy happy handsome."

Alongside her words, Katherine also shared a gallery of intimate photos of Pratt throughout the year, including pics of the two posing together and one of Pratt holding his wife in his arms for a kiss.

Pratt and Katherine have been married since 2019, they welcomed their second daughter Eloise Christina in May.