By Mark Mcgreal For Dailymail.Com

Published: 18:35 EDT, 30 July 2022 | Updated: 18:37 EDT, 30 July 2022

Katherine Schwarzenegger and Chris Pratt each posted to Instagram in honor of Arnold Schwarzenegger's 75th birthday on Saturday.

The Terminator star's oldest child Katherine, 32, shared several throwback photos. In the first, she and her father rode horses together. 

She wore a pink sweater under a light blue shirt, left unbuttoned. She smiled wide while her father put his fingers up in 'bunny ears' above her head. 

Birthday post: Katherine Schwarzenegger and Chris Pratt each posted to Instagram in honor of Arnold Schwarzenegger's 75th birthday

Arnold wore a light blue button-down shirt, matching jeans and a white T-shirt underneath his button down. 

In the next snap, Arnold and Katherine played around in the pool, with the children's author slung over her strapping father's shoulders.

Another photo showed Arnold holding two of his children up on his shoulders, tightly to his body.

Pool day: In the next snap, Arnold and Katherine played around in the pool, the children's author slung over her strapping father's shoulders

Holding up her kids: Another photo showed Arnold holding two of his children up on his shoulders, tightly to his body

All black: The final snap showed Arnold walking away from the camera in a black leather jacket and jeans with a small child resting on his right arm

The final snap showed Arnold walking away from the camera in a black leather jacket and jeans with a small child resting on his right arm. 

The USC alumna captioned the series of photos, 'Happy birthday daddy!! We love you so much! You’re the best and most fun opa and dad and we are all so lucky to have you in our lives! Happy happy!!'

Pratt's post in honor of his new father-in-law showed a more recent image of the two men. 

They stood side by side, cigars in hand, while looking relaxed in lightweight T-shirts. Schwarzenegger's shirt read 'Made in the U.S.A.' with a large white eagle on the chest while Pratt's black shirt read, 'walk in love.' 

In law: Pratt's post in honor of his new father-in-law showed a more recent image of the two men

Another post for the father: In Baena's snap, his dad held his shoulders from behind. They both wore all black clothes in the picture

Pratt captioned the snap, 'Happy birthday to the man, the myth, and the legend. Love you @schwarzenegger!'

Pratt and Schwarzenegger started dating back in 2018. They married the following year and share two children together. 

Two of Arnold's other children, Joseph Baena and Patrick Schwarzenegger also shared posts to honor their father on his big day. 

In Baena's snap, his dad held his shoulders from behind. They both wore all black clothes in the picture. 

Baena captioned the photo, 'Happy Birthday Dad! Thank you for inspiring me and others around the world to be better every day. I love you and I hope you have the best day. Cheers to 75 years young.' 

Stylist: Patrick shared a number of snaps which started with a photo of his dad cutting his hair. He looked quite nervous in the photo

A trio of superstars: The next shot showed a throwback photo of his dad with Risky Business actor Tom Cruise and Philadelphia star Tom Hanks

Individual shots: Patrick shared a couple photos in single shots by himself

Patrick shared a number of snaps which started with a photo of his dad cutting his hair. He looked quite nervous in the photo. 

The next shot showed a throwback photo of his dad with Risky Business actor Tom Cruise and Philadelphia star Tom Hanks. 

Arnold held a small brown dog in his arms in one photo and smoked a cigar during another. 

The final shot showed Patrick and Arnold dressed in Western outfits, cigars in their mouths and cards in hand. They toasted with a pair of what appeared to be alcoholic beverages.  

Father and son: The final shot showed Patrick and Arnold dressed in Western outfits, cigars in their mouths and cards in hand

Remembering his mom: While other people extended their well wishes to Arnold on his birthday, he was more interested in keeping the spotlight on someone else

Aurelia: He tweeted out a tribute to his late mother Aurelia, who would've turned 100 years old on Saturday

Heartfelt: The Predator actor shared several old photos with his late mother and wrote a heartfelt caption that read, 'Today my mother, Aurelia, would have been 100. She was the best mother you can imagine and I’ll always love her'

Meaningful: 'I can’t explain how much she meant to me, but she is the number one reason I won’t call myself self-made'

'Unconditional': 'She showed me unconditional love, the importance of keeping my house clean, how to make the perfect schnitzel, and patience'

While other people extended their well wishes to Arnold on his birthday, he was more interested in keeping the spotlight on someone else.

He tweeted out a tribute to his late mother Aurelia, who would've turned 100 years old on Saturday. 

The Predator actor shared several old photos with his late mother and wrote a heartfelt caption that read, 'Today my mother, Aurelia, would have been 100. She was the best mother you can imagine and I’ll always love her. I can’t explain how much she meant to me, but she is the number one reason I won’t call myself self-made.'

He continued, 'She showed me unconditional love, the importance of keeping my house clean, how to make the perfect schnitzel, and patience. A lot of patience. Make sure to tell your mothers how much they mean to you!'

Let your mother know: 'Make sure to tell your mothers how much they mean to you!' he finished off his long caption

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Published by Associated Newspapers Ltd

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