If only there was a mathematical formula for telling you how long it would be before they hate you.

Having two children at both ends of the scale gives me a headache. I have a two year old who still thinks I am the centre of his universe and a teenager who once thought I was the centre of her universe but now would rather I didn't speak for fear of embarrassing her. It's hard, as a parent, to accept that your children no longer view you as anything other than an open wallet. That adorable little girl I once spent hours playing Barbie with now thinks I know nothing, have terrible dress sense, a bad hairstyle and say the most ridiculous things. This doesn't stop her from asking me to buy her things several times a day, each and every day.

Just the other day she feigned some terrible illness and came home from school early. Her terrible illness didn't stop her from browsing online stores and ebay and asking me to buy all those things she "can't possibly live without" or "has been desperately wanting like, forever". I told her if she didn't want to hear the word "no" then she simply shouldn't ask. Of course that was like telling her I was having the internet access cancelled until further notice. She stormed off screaming something about me never buying her anything despite the fact that she's managed to wrangle a whole new wardrobe out of me, her father and her aunt this winter. More than anyone else in this house has had for years.

The next morning she deliberately slept in late in the hope I may believe she wasn't feeling so well. I banged on her bedroom door and made her get up. She came upstairs trying very hard to look ill and asked me if she could just have the morning off to rest before her math exam at midday as she felt so bad. The penny dropped immediately. A math exam! That's what the illness was all about. I sat very quiet for a few minutes to let the tension build and let her believe that I may seriously be considering allowing her to stay home and rest. Then I let her down with the sad news. "No". She stomped off, slamming doors as she went. Then she came back, crying and said "You know mum, I never wanted to say this but I hate you right now".

Then I looked at Henry who was sitting on my lap reading his truck book. He looked at me with love, devotion and affection. I'm going to have to treasure these next few years because soon enough it will be him telling me he hates me because I won't buy him a fully functioning bulldozer.