Kirk Douglas said he hoped his grandson's acting career would resume
Veteran film star Kirk Douglas has asked a US judge to give his grandson a lenient sentence for drug-dealing.
The 93-year-old said in letters submitted to court that he wanted to see Cameron - the son of actor Michael - turn his life around "before I die".
The 31-year-old's stepmother Catherine Zeta Jones also expressed her support in a letter, calling him "a considerate, worthy human being".
Douglas faces a minimum prison sentence of 10 years for dealing Class A drugs.
His lawyers argue that his sentence, which is due to be passed next week, should be only three and a half years because he has kicked his heroin addiction.
Kirk Douglas added in his letter that he had travelled from Los Angeles to New York to visit his grandson in prison, saying "at 93, that's a long trip".
Cameron Douglas was arrested in 2008
"He didn't express any self-pity, nor did he ask for any," he said. "The only sorrow he expressed was for the trouble he had caused others. ... I was shocked when he got in such a mess."
The screen star's letter concluded: "I'm convinced Cameron could be a fine actor. ... I hope I can see that happen before I die. I love Cameron."
Douglas pleaded guilty to dealing methamphetamine and cocaine from an upmarket New York hotel in court earlier this year.
He was arrested in July 2008 and had been paid thousands of dollars for smuggling the drug between various parts of the US. He was also charged with heroin possession.
Douglas appeared in a number of films including It Runs In The Family, which also starred his father and grandfather.