We're in a garden centre, and Noah's tugging on the trees. They're Christmas trees, and as his tiny chubby three-year-old hands pull on the branches he shakes a bunch of needles onto the floor.
"Noah!" I hiss. "If you do that again, we'll go straight home!"
Instantly, I regret what I've said; not because I've pulled my angry face (which could frighten the hardiest of children), but because I've done what I swore I would never do as a parent: I've made a hollow threat.
There's no way we're going home, even if he does carry on being naughty, because we're there to see Father Christmas and we've paid good money to do so. Plus, in going home I'd be punishing our eldest son, Isaac, despite the fact that he's done nothing wrong.
Fortunately, Noah doesn't call my bluff, and starts to behave; but my regret lingers. So many times I've heard other parents bellow hollow threats at their children, and I've seen how much it erodes their control and power when the child eventually learns that what the parent is threatening will never happen.
"Finish your plate of food or you won't have any pudding," says someone I know (mentioning no names, although if they do find out and threaten me I know they'll be fibbing). The child doesn't finish their plate of food, yet is still given pudding. Time after time this happens, and now the child is older and whenever he hears the same feeble threat he just laughs and puts down his fork.
It's an easy spiral to fall into, and it all stems from the fact that we parents are so exhausted that there are often times when we would rather just have an easy life than plough all our energy into...well, parenting. Not giving this child pudding would have resulted in tantrums, screaming, hours of stress and arguments; and so, sometimes, giving in is just easier.
But easier is rarely better, and in a world where children are not children for long it's important for parents to maintain control for as long as possible - and to do this we need to follow through with our threats (and our promises, for that matter).
I remember my mum once telling me a story of how, when she was a child, she was being naughty at the dinner table.
"If you're naughty one more time," her father told her, "I'll pour this bowl of baked beans over your head."
Perhaps ignoring him, perhaps testing him, my mum was naughty again. Five seconds later, she was feeling the discomfort of baked beans in tomato sauce sliding slowly down the back of her neck. She thought twice before being cheeky again...