Panic over - she smiled, and expected my brother and me to share her relief. We're so inured to this ritual we barely bothered to raise an eyebrow. Perhaps we would have if the drama had differed at all from her performance over the last two decades. Instead, you could have set you're watch by the pre-lunch exchange.
Probably the single biggest let-down about Christmas with my parents is myself. I despise the inevitability of my 48-hour regression into a monosyllabic, stroppy teenager who, once settled in the family bosom, can only communicate in a series of grunts, whinges and cynically negative put-downs. Whereas my parents always stay the same, I alter quite drastically.
Staying with them at other times, I can just about keep a grip on my adult persona, but at Christmas the infant takes control. It kicks in around the second day with a point-blank refusal to put up any more Christmas decorations. "What about some tinsel round the pictures - like you used to do when your were at home?" entreats my mother. "No, Mum, the room looks better without them," I say, slumped on the sofa, eyes glued to This Is Your Life. "Would you like a gin and tonic, dear? I'm having one." "Yup," I reply and surprise myself by saying Please.
Four hours later and my mouth is set into a perma-scowl; one hand welded to the remote control, the other to the gin and tonic. I'm catatonic, deadened by a lethal cocktail of predictability. The Morecambe and Wise repeat: "Wasn't the big one lovely?" and "You forget what a good dancer the little one was." The Two Ronnies repeat: "Never as funny as the other two." Everything's a repeat at Christmas, including my own childish responses. Partly, it's because spending concentrated time with parents in your early thirties seems somehow unnatural. When you're not yet a parent it's harder to act like a grown-up in their presence. It's not a role they expect from you, so you resort to one that's taken 15 years to perfect; the whingeing adolescent.
Christmas Eve, I break with tradition and offer to cook my mother a meal - as long as she stays out of the kitchen. Within five minutes she pushes her head round the door. "Mum," my voice is a petulant whine. "I can manage on my own." "I just wanted some mineral water. I wasn't going to interfere," she says, walking to the fridge. She hovers, scrutinising my gloopy-looking cheese sauce bubbling on the hob. "Look," I snap. "Please let me get on with this myself." I feel her eyes on me as I hack through an onion. "There's a sharper knife than that on the draining board. It's much easier than that blunt old thing." "I'm absolutely fine with this one," I snap, reaching for the sharper knife without her noticing. She leaves me to it and I feel churlish that I can't accept her advice gracefully.
Later on we sit down as a family to watch TV and my mother, mid-laugh, glances from the TV screen to me. Her look implores, "Isn't this hysterical? Why don't you laugh along with your father and me?" Ignoring her attentive stares, I grit my teeth and look deeply bored. My brother flicks to Reeves and Mortimer and my parents look acutely baffled. I affect a raucous laugh. "Don't know what the fuss is about these two," my father mumbles, leaving the room closely followed by my mother.
Later on, my brother and I slink out to visit friends, lighting up cigarettes on the doorstep as we go. "That's it," I say firmly, in time-honoured tradition. "The last Christmas I'll ever spend at home - next year I'll be doing something completely different." If only it were true. Instead, I chew my top lip and resign myself to being more predictable than my parents.
The next day there are fond embraces when I leave. The relief that Christmas is finally over sinks in as I shut the car door and watch their smiling faces diminish in the rear-view mirror. The taste of freedom may be swiftly tainted with guilt, but for a few seconds the journey back to adulthood seems blissful.
What the parents say ...
Dorothy Morris, 74, retired teacher, and husband Albert, 76, retired solicitor: Michael is 36 and he's come home every year since his wife left him. He arrives on Christmas Eve and leaves on Boxing Day, and it's three days of misery. He's got a good job, but he just feels sorry for himself all the time. It's terribly hard making jolly conversation with someone who's determined to be miserable.
Susan Baxter, 43, shop assistant, and husband Stephen, 45, builder: Louise has been at art college for two years now. She came home again this year and in some ways we weren't looking forward to it, even though we love her very much. We're not trendy, we're middle-aged people who like our home comforts. Louise has got all these wild ideas about decor and taste and always goes on about how the house is done out. It really annoys me and we always have an argument about it, especially over the decorations.
Dorothy Samuels, 53, office administrator: It's not so much my daughter as my son-in law who's a problem at Christmas. He lets the kids run riot, helps himself to the remote control and the contents of the fridge, and completely ignores the fact he's staying in my house. Because I'm a widow there's no man to put him in his place. I can never understand why my daughter married him - her father was never like that.
Janet Moodie, 58, painter: My children are all adults nearing their 40s but when they come home for Christmas they revert to being teenagers. All the squabbles they used to have 20 years ago come back and old gripes resurface like they'd never been away. I've moved on and I expect them to have moved on. They expect me to make an effort at Christmas because I always have, but I find the catering financially and physically stressful. Yet pride won't let me fall by the wayside.
Patricia Stowe, 62, receptionist, and husband Brian, 63, retired police officer: This year, two of my three daughters settled back home after living abroad for years. The third joined the Royal Navy this year and she came home for Christmas, too. It was weird because we're so used to being on our own. As you get older, you get set in your ways and the girls are used to running their own homes. We all had to adapt - not easy.