Chris Hemsworth Pokes Fun at Brother Liam on His Birthday: 'Get in Shape and Take Care of Yourself'

Chris Hemsworth is poking fun at younger brother Liam Hemsworth in a silly birthday message.

The Hunger Games star turns 32 on Thursday, and on Instagram, Chris, 38, shared a shirtless photo of Liam, joking in the caption that "hopefully" this year he will "finally" get into shape. The Thor actor even offered his sibling a "family discount" to his fitness training program, Centr.

"Happy birthday @liamhemsworth hopefully this is the year you finally get in shape and take care of yourself 😂💪 To help with your transformation I'm gonna gift you 10% off a @centrfit membership #familydiscount," Chris wrote. "love you."

He also included a photo of Liam giving thumbs up next to gifts, balloons and a birthday cake, plus a throwback photo of the star as a kid.

In a video on his own Instagram page, Liam smiled while giving a "special thank you" to Chris for the discount: "Really appreciate it, mate. That's just the kick in the ass I needed to continue on my fitness journey. Here's to a happy, healthy year, everyone. Lots of love."

"Thanks to everyone who sent me birthday wishes! Love you all!" he wrote in the caption. "These cakes that I also got sent should really help on my health and fitness journey! Cheers guys!"

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Chris is known to have a laugh with Liam on social media. In December, he shared photos shaking hands with his brother, calling him one of his fans — named "Leon."

"Always great interacting with my fans. Met this young lad recently, reminded me of my younger self," he wrote. "Not in looks, but just a real go getter attitude. He insisted on the resemblance and I assured him no one else has this look. Was great to meet you Leon good luck in the future."

For Chris's birthday in August, his brothers Liam and Luke, 41, got him back by trolling him on Instagram. Liam wrote "Happy birthday @chrishemsworth" next to a photo of himself with Luke rather than posting a picture of Chris. Chris replied to his brothers, going along with the joke, writing in the comments of Liam's post, "I'm the best photographer going [sic] round."

Luke also pranked Chris by posting a selfie of himself and Liam while wishing the Avengers star a happy birthday.

"Happy birthday brother @chrishemsworth!! Love you mate will remember this trip the Kimberly region for ever. So many memories together," Luke wrote, adding a laughing emoji. "Yeh it was so much fun, kinda felt like a dream, kinda like I wasn't even there," Chris joked back.