Catherine Zeta-Jones and Kirk Douglas have written to a judge to ask for Cameron Douglas to be given a lesser sentence.

The Hollywood veteran, who is Cameron's grandfather, and his actress daughter-in-law - who is married to Cameron's father Michael Douglas - have sent a heartfelt letter to Judge Richard Berman defending his character and asking the judge to be lenient when he hands down his punishment to the 31 year old for drug possession and dealing.

The 93-year-old actor wrote: "I remember when he played a part in the movie 'It Runs in the Family' with me and Michael in 2003. He was a natural. We were so proud.

"Of course, as his grandfather - by the way he calls me Pappy (never grandpa) - I am prejudiced. I was shocked when he got in such a mess... I am convinced that Cameron could be a fine actor and a person that cares for others. I hope I can see that happen before I die. I love Cameron."

Cameron is facing a possible 10 years in jail after pleading guilty in January to possession and dealing methamphetamine and cocaine from a Manhattan hotel last July.

The actor has also been praised as a fantastic step-brother by his stepmother Catherine, who has two children, son Dylan, nine, and six-year-old daughter Carys, with Michael.

The 'Chicago' actress personally urged the judge to help rehabilitate him rather than punish him for his actions.

Her testimonial wrote: "My stepson is a caring, considerate, worthy human being, but nevertheless, the disease that for years he has tried to combat, did take over again.

"What is wrong is wrong, but may all these positive attributes prevail, so that a facility that he is positioned in will help rehabilitate him."

The letter also included a note from Cameron's mother Diandra - who divorced Michael in 2000 - in which she spoke about her son's recent "enthusiastic" change in demeanour.

She added: "Cameron's arrest has brought all of us life lessons, most of all Cameron. As painful as it is for a mother to have to watch her son go through an ordeal such as this one... for the first time in my life I see my son enthusiastic about his life."

Cameron is currently being held at the Metropolitan Correctional Center in New York City, ahead of his sentencing on April 27.

The letter also contained personal messages from other family members.