Stepfather of Audrina Patridge's Late Niece Sadie Speaks Out After Her Death at 15: 'My First Love'

Audrina Patridge's family is continuing to mourn the death of Sadie Raine Loza.

On Wednesday, the teen's stepfather Kyle Loza shared a tribute to Sadie on social media following news of her death.

"Baby girl- I will carry your memory with me until I see you again," he shared alongside a photo of his late stepdaughter. "I can't stop thinking about you. I'll never stop loving you and I would do anything to laugh with you one more time. You were my first Love."

He signed the tribute "[Love] Dad" and also added "NSD," which appears to be an abbreviation for "Never Say Die," which is also the name of Kyle's tarot card business.

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Patridge, 37, also mourned the loss of her niece by sharing a carousel that featured special moments shared between her and Sadie over the years.

In the caption, The Hills alum wrote, "My heart hurts to even write this. My beautiful niece is now in heaven."

She continued, "I know [it's] not goodbye forever, but it is the hardest to say goodbye for now."

Ending with a message for Sadie, Patridge said, "We will miss you and cherish every single moment we had with you. Rest in peace Say Say!! We love you forever & ever! ✨🤍🙏."

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The reality star received support in the comments section from her Hills costars, including Brody Jenner, who wrote, "So so sorry for your loss Audrina. This is heartbreaking. Sending love to you and the family."

Kristin Cavallari commented, "Omgggg this kills me."

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Audrina Patridge/instagram

Shortly before Patridge's post, her sister — Sadie's mother, Casey Loza — shared the news of Sadie's death.

"Sadie Raine Loza has left this Earth for the heavens," she captioned a selfie of her late daughter. "Writing this was the hardest thing I ever have had to do, not knowing the right words I'll leave you with this, Sadie liked to remind me that the first law of thermodynamics aka (Law of Conservation of Energy) works in all spheres of life…..'Energy cannot be created or destroyed, it can only be changed from one form to another.' "

She shared how Sadie's legacy will live on, writing: "Transformation is a better word than death. Her story will save countless lives, her memory will never be forgotten. Rest In Peace you brilliant starseed. You're with your creator. We will miss you dearly. I love you."

"❤️❤️😢😢," Patridge wrote in the comments section.

Sadie's cause of death has not been made public.