‘My heart hurts’: The Hills star Audrina Patridge announces death of 15-year-old niece

The Hills star Audrina Patridge has announced the death of her 15-year-old niece, Sadie.

Patridge, who featured in all six seasons of the MTV reality series, shared the news on social media on Tuesday (14 February).

She posted a selection of photos and videos of Sadie at different ages in her tribute.

“My heart hurts to even write this. My beautiful niece is now in heaven,” the caption to her post began.

“I know it’s not goodbye forever, but it is the hardest to say goodbye for now. We will miss you and cherish every single moment we had with you.

“Rest in peace Say Say!! We love you forever & ever!”

In response to the sad news, friends and fans of the reality star contributed messages of support in the comments section.

Brody Jenner, who co-starred with Patridge on The Hills, wrote: “So so sorry for your loss Audrina. This is heartbreaking. Sending love to you and the family.”

Meanwhile, their fellow former castmate Kristin Cavallari reacted with: “Omgggg this kills me.”

“Audrina! I’m so so sorry! Sending all the love and light to you and your family,” replied Rachel Bilson, while Twilight actor Ashley Greene added: “Sending you and your family lots of love.”

One of the posts in Patridge’s tribute featured a video of her with Sadie and her mother, Casey Loza, who made occasional guest appearances on The Hills and spin-off series The Hills: New Beginnings.

Neither Patridge, nor her sister Loza, have shared details of the cause of Sadie’s death.

In her own Instagram post, Loza wrote that her daughter’s “story will save countless lives”.