The actress posted a touching tribute to her Jessie costar on Instagram Sunday night, sharing a video of Boyce urging fans to use social media to “make the world a better place.”
“It’s crazy, we can tweet whenever we want and we can use social media and Instagram and make the world a better place,” Boyce says in the clip posted to Ryan’s Instagram Story. “Instead of a worse one, which so many people use it for.”
The clip is taken from Boyce’s acceptance speech at the 2018 Thirst Gala for the Pioneering Spirit award. Boyce was a longtime advocate for the non-profit organization Thirst Project, which raises awareness about the global water crisis.
“We need to use what we have and make the world a better place for other people, other people, people who need us,” Boyce concluded.
Ryan and Boyce starred together on the Disney sitcom Jessie, which ran for four seasons from 2011-2015.
Boyce died in his sleep Saturday morning of a seizure brought on by an “ongoing medical condition,” a family spokesperson said. He was 20.
“He passed away in his sleep due to a seizure which was a result of an ongoing medical condition for which he was being treated. The world is now undoubtedly without one of its brightest lights, but his spirit will live on through the kindness and compassion of all who knew and loved him,” a family spokesperson said in a statement obtained by PEOPLE.
“We are utterly heartbroken and ask for privacy during this immensely difficult time as we grieve the loss of our precious son and brother.“
Along with Ryan, Peyton List, who played Boyce’s sibling on Jessie, mourned his death in a heartbreaking Instagram post. “He was younger than me but taught me how to spread love and kindness more than anyone that has ever been in my life,” she wrote.
“There is a hole in my heart that will never heal left for you. I will never stop talking about you,” she added.
Boyce’s TV dad on Jessie, Charles Esten, wrote a series of tweets remembering his costar. “My family and I are devastated today, by the loss of our young and amazing friend, Cameron Boyce. Years before I was blessed to play his father on JESSIE, we were blessed to know him and his wonderful family at the elementary school our kids all attended together,” he said. “It was there we were introduced to his endless talent, kindness, and joy for living. At his very 1st talent show, little Cameron’s dancing lit up the stage, and left everyone on their feet, cheering. It was clear to all that he was destined to be the star he would soon become.”
Disney also released a statement, calling Boyce a “remarkably caring and thoughtful person.”
“From a young age, Cameron Boyce dreamed of sharing his extraordinary artistic talents with the world. As a young man, he was fueled by a strong desire to make a difference in peoples’ lives through his humanitarian work,” a Disney Channel spokesperson said in a statement obtained by PEOPLE. “He was an incredibly talented performer, a remarkably caring and thoughtful person and, above all else, he was a loving and dedicated son, brother, grandson and friend. We offer our deepest condolences to his family, castmates and colleagues and join his many millions of fans in grieving his untimely passing. He will be dearly missed.”
Along with Jessie, the Los Angeles-born actor was best known for his role as Cruella de Vil’s son in the Descendants TV movies.