More details about the death of the Real Housewives of Orange County alum Lauri Peterson's son Josh Waring are being released.

In a tribute to the 35-year-old, who died March 31, his older sister Ashley Zarlin spoke out about his lengthy struggle with substance abuse.

"On Easter Sunday, I lost my brother to the relentless grip of addiction," the 39-year-old wrote on Instagram April 6, alongside childhood photos of the two. "It's a disease that distorts and destroys, leaving behind shattered dreams and broken hearts."

She continued, "He was brilliant and had limitless potential, but addiction veered him off course. My heart aches for the lost opportunities for us to grow together as adults, to share laughter and dreams, the conversations that we will never get to have, and the dreams that will be left unfulfilled. My thoughts linger on the what-ifs, the alternate paths he could have taken if only the system had offered more than empty promises and closed doors."

Lauri, an original cast member of RHOC, had appeared with Ashley, Josh and their sister Sophie, 26, on the Bravo reality show before she left the series in 2013. Josh's addiction battle and some of his legal turmoil were depicted in the first four seasons between 2006 and 2009.

He would go on to serve four years in prison for assault until his release in 2020. In 2022, he was sentenced to two years in prison, with credit given for 106 days in custody, after pleading guilty to drug charges. This past February, he was arrested on suspicion of punching a security guard at a hospital.

"My mom's unwavering love and tireless efforts to support him will forever be etched in my heart," Ashley wrote. "She fought alongside him, never wavering in her belief that he could overcome this demon. I wish for a different outcome with every fiber of my being. I wish I could have done more, been more, to help him find his way back to the light. As I grieve his loss, I cherish the memories of who he truly was, before addiction stole him away. My little brother."

Ashley called for healthcare reform "that prioritizes compassion and support." She then shared a personal message for her late brother.

"Josh, I hope that you've finally found the peace you've been looking for," she said. "You're no longer in pain, you can rest. I love you xo Smash."

Lauri, who has also raised Josh's daughter Kennady, 11, since she was a baby, had announced her son's death April 6. While the cause of his death was not made public, she did note his addiction battle.

"Josh fought every single day for most of his adult life, for his life," the 63-year-old wrote on Instagram, "but this past Sunday, the challenge was too great."

Lauri continued, "Not everyone understands those suffering from substance abuse disorder, but I am forever grateful for your understanding and the impact you made on his life. I also thank those who have supported me through this journey and offering kind words of encouragement by sharing their stories of living with substance abuse disorder and the many parents that have shared their stories over the years with me about the children they have sadly lost due to this illness."

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