JAMES MCCARTNEY:“MY RELATIONSHIP WITH HEATHER MILLS WAS NOT VERY GOOD.I DIDN´T LIKE HER”... “NANCY’S MY NEW MOTHER.I FEEL THAT.DEFINITELY.SHE’S VERY GENUINE.SHE MAKES DAD VERY VERY HAPPY.WE ALL ADORE HER”

James McCartney has spoken candidly for the first time about his drug addiction and the difficult relationship he had with former step-mother Heather Mills..

“We were both grieving together. That first night, in Arizona, when she’d just died I thought it would be too sad for Dad to sleep on his own so I kept him company,”.

James, 35-year-old musician, previously shunned the limelight unlike his sisters fashion designer Stella and photographer Mary. He admitted to alienating himself from his family following the death of his mother Linda in 1998, but says he has now “re-bonded” with his father and even played on two of Sir Paul’s solo albums.

The musician, who is currently trying to break America with a 42-date tour, said in an interview that he was so grief-stricken following his mother's death that he slept in his father Sir Paul's bed.

His mother Linda's death, he said, “was very detrimental to my relationship with my family” and resulted in him being admitted to a rehabilitation centre in Arizona for drug dependency. He has since suffered from drugs and alcohol addictions, but says he has been sober for the last seven months.

He admitted that he "didn't like" Heather Mills, whom his Beatle father married in 2002 and divorced in 2008.

“My relationship with Heather was not very good. I didn’t like her,” he said. “But I wouldn’t want to say anything negative about her because she’s good mother to Beatrice [Sir Paul’s daughter by Mills] and that’s the most important thing.”

He said his relationship with Sir Paul’s current wife Nancy Shevell is much better. “Nancy’s my new mother. I feel that. Definitely. She’s very genuine. I knew her a year or so before she married Dad.

“She had been one of the biggest supporters of me pursuing my own dreams. She wants me to have my own career. She makes Dad very, very happy. We all adore her.”

McCartney’s decision to go into the music industry was not always clear-cut, he said. “It’s hard to live up to The Beatles. Even Dad found it hard living up to The Beatles. I started out playing under an alias because I wanted to start quietly.”

He said he does not want to be “the new Paul” but is striving to be the best he can. “Music is in me. I don’t have much of a choice. People might listen to one of my songs or come and see my because of my famous last name, but if my music’s not good they won’t hang around.”