Kaia Gerber leads tributes as rising actor Daniel Mickelson dies aged 23

Kaia Gerber has paid tribute to 23-year-old rising actor Daniel Mickelson following his tragic death.

Daniel's sister Meredith broke the news of his passing in a post on her Instagram page on Monday, revealing he had died the day before but declining to reveal a cause of death.

"My heart is shattered & to write this feels so wrong and i don't even know what to say," she wrote. "Yesterday i lost my brother, best friend & the other half of my heart. There wasn't a person i loved more on this earth. theres no words that can do him justice that i could write. to know him was to love him. he was the happiest brightest smiley most sunshine human to exist and I'm so happy God chose me to be his sister for his whole amazing life (sic)."

Following her heartbreaking post, model Kaia was quick to offer her memories of Daniel - who had just started making a name for himself in Hollywood with roles in series Mani and horror film The Killer Clown Meets the Candy Man.

"I remember that time we sat on the couch and spent the whole day coming up with our own secret language that we continued to speak every time we saw each other," Kaia wrote on her Instagram Stories. "I wish we could go back there. I wish we were still talking in sentences that probably annoyed everyone else but made us crack up every time.

"I wish I was still sitting on my bathroom floor FaceTiming you, because that was the only place I had wifi and I never wanted to miss a call from you. thank you for being the reason for so much laughter and happiness in the world. it won't be the same without you here. I love you Daniel."

Patrick Schwarzenegger, Paris Hilton, Madison Beer and Zedd were among the other stars offering their condolences following Daniel's death.