Smash hit

My father, Peter Sidney Lawford, was English, Protestant and an actor, three characteristics that made my grandfather's skin crawl. When my father flew to New York to formally ask if he could marry my mother, my grandfather supposedly said: "If there's anything I'd hate more for a son-in-law than an actor, it's a British actor!" He ultimately approved the marriage, if only because he couldn't prevent it.

My father and my mom had moved into a small two-bedroom place on the beach in Malibu soon after their marriage, but dad had no idea how to deal with a pregnant wife and my eventual arrival. So he left, citing his need to be closer to work, to stay with a friend. My mom showed up a few days later. She told my dad that he wasn't getting rid of her that easily. I was already causing panic in my parents, and I wasn't even here yet.

My mother and father used to hang out with their friends at the Beachcomber bar on Channel Road in Santa Monica. Legend has it that we stopped there on the drive home from the hospital, with my parents proudly placing their newborn son on the bar and ordering their favourite cocktails. I wonder if this was when the imprint of alcoholism found me. Or did it always run in my blood? We had privilege, power and wealth. What we didn't know was that alcoholism ignores all that.

I was christened a month later by Cardinal Francis McIntyre in Santa Monica. My mom showed up with her father and a cheque for $100,000 — I'm sure all those zeros had something to do with the good cardinal showing up to do the honours. My father's mother, Lady May Lawford, also attended, and managed not to make a spectacle of herself by dissing either me, my father or the Kennedys, which was a minor miracle. If my father was my grandfather's worst nightmare, my mother was Lady May's.

To her the Kennedys were "barefoot Irish peasants" and my mother was "a bitch" who had trapped her beloved son into marriage.

Lady May was the kind of crazy relative you wanted to keep locked in the cellar. Embarrassing moments were her speciality. There was the time she hired an elephant, put a big Vote for Nixon sign on it and rode it down Hollywood Boulevard. Or the time she telephoned Louis B Mayer himself and, just for laughs, told him that my dad was a homosexual. She had flair, drank too much, and drove my dad nuts. Lady Lawford might have been nuts but she was a Lady. She wore fur collars and hats.

To me she was some sort of British royalty. She had that air about her of thinking she was better than anybody, and she knew she was better than the Kennedys. From day one she had groomed my dad for stardom and marriage to European royalty, not the ersatz American variety.

If you believed the hype, my parents' marriage was storybook. There were the presidential visits, the Rat Pack, Marilyn, weekly poker games with Hollywood's biggest and brightest, Vegas, Palm Springs, helicopters to work and an extra limo just for the bags whenever they travelled.

Soon after I got home from securing my spot in a Catholic cemetery with my celebrated baptism, my father, who had been an only child and was desperately clinging to the remnants of his sacred beach life, decided that having a newborn in the house wasn't going to work for him. I imagine a conversation that went something like this: "Pat, he cries all the time.

I can't show up on the set with bags under my eyes. Plus the house smells like shit — it's getting into my clothes. Why don't we rent the apartment across the street for him?"

My mother wanted her marriage to work, so at the tender age of two months I got a place of my own, a couple of doors down from my family house, nice and cosy for me and the nanny.

My parents had separate bedrooms. I would go to visit them when my mom was watching the news with Walter Cronkite and my dad was getting dressed for the evening festivities, but once the door leading to their wing of the house was closed, it was not a door any kid would want to open. It was dark, and both my parents slept hard. My mom in a king-sized bed with blinders over her eyes and all the windows open, so the breeze from the ocean was blowing the curtains all over the place — like a wall of dancing ghosts.

I would stand there at the side of her bed whispering: "Mummy, are you awake?" She rarely stirred. There is something terrifying in being unable to wake up a parent.

Times recommends

• Tewkesbury: when the memories flood back
• How I lost the gift of joy for a while
• The A-Z of winter style rules