'Too young': Adam Sandler mourns death of on-screen son Cameron Boyce

Adam Sandler is mourning actor Cameron Boyce, who played his son in the Grown Ups movies, after it was announced the 20-year-old died in his sleep on July 6.

Boyce, also known for his work on TV show Jessie and the Disney film franchise Descendants, had a seizure as a result of an on-going medical problem, according to a family spokesperson.

After the news broke, Sandler posted a black and white photo of his co-star with a touching tribute.

"Too young. Too sweet. Too funny," he wrote.

"Just the nicest, most talented, and most decent kid around. Loved that kid. Cared so much about his family. Cared so much about the world.

"Thank you, Cameron, for all you gave to us. So much more was on the way. All our hearts are broken. Thinking of your amazing family and sending our deepest condolences."

Disney Chief executive Bob Iger also tweeted that Boyce was "far too young to die", saying he was a friend to many at Disney.