The smash hit Sunday Times bestseller.Tuesday 8th SeptemberFirst day back at school. I am going to 100% nail being a school mummy this year. I can totally do this. Yes, this year is definitely going to be much better – I am absolutely not going to shout at the children, let them stuff their faces with crisps or goggle away on the iPad.And I most certainly will not slump on the sofa at the end of the day, glugging wine and muttering ‘FML’ repeatedly.Unfortunately I have not yet actually managed to buy the bento boxes for their lunches or book jiu jitsu lessons, and I will have to learn to like green tea, as it is foul, and I have not yet mastered French plaits, but I am quietly confident that these are mere details in my grand master plan…It is Mummy’s 39th birthday.She is staring down the barrel of a future of people asking if she wants to come to their advanced yoga classes, and polite book clubs where everyone claims to be tiddly after a glass of Pinot Grigio and says things like ‘Oo