![Liam Hemsworth](https://cdn.statically.io/img/people.com/thmb/ruk4VvAntgpaALosVjd3rt8RmQc=/1500x0/filters:no_upscale():max_bytes(150000):strip_icc():focal(679x719:681x721)/Liam-Hemsworth69-b30fe0c5f6ea42c18a2efe2429108c7e.jpg)
Liam Hemsworth's girlfriend quietly celebrated the actor's birthday in a special way.
Model Gabriella Brooks, 25, shared a black-and-white shirtless photo of Liam playing with their dog with the words "birthday boy" written over it on her Instagram Story on Thursday.
Liam, who turned 32, appeared in a second photo on Brooks' Instagram Story in which she shared a black-and-white selfie of the two together.
The Hunger Games actor thanked his family, friends and fans for their birthday wishes in a video posted to his Instagram, writing in the caption, "Love you all! These cakes that I also got sent should really help on my health and fitness journey! Cheers guys!"
In the clip, the actor also thanked his older brother, Chris Hemsworth, for giving him a membership to Chris' fitness app, Centr.
![Liam Hemsworth](https://people.com/thmb/8ZRAOb_0HOdKDj7OETunEbeog9s=/4000x0/filters:no_upscale():max_bytes(150000):strip_icc():focal(749x0:751x2)/Liam-Hemsworth70-7414a3ced91143bbb6d465e07f4fcff1.jpg)
"Special thank you to my brother Chris for giving me 10% off on a Centr fit membership," Liam said. "I mean, what a gift, the gift of health. Really appreciate it mate, just the kick in the a-- that I needed to continue on my fitness journey."
Chris simply responded in the comments section, "😂😂😂."
Earlier in the day, 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.
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"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 the thumbs up next to gifts, balloons and a birthday cake, plus a throwback photo of his brother as a child.