The mother in this series can only be a projection of the author, and I'm reassured to see that she isn't always perfect. In this book, the kids are getting ready to go back to school. They're having breakfast, and Max is going through all the good resolutions he's made about being more focussed and productive this term.
Then - oops! - he knocks over his bowl of drinking chocolate and spills it everywhere. Mom snaps at him before she's had time to think: he could start by being focussed and productive enough not to get chocolate all over the tablecloth. Dad defends him by saying that he's sure his Max will do brilliantly this term. He's going to be first in the class! But Mom, who's still mad, says they can all stop kidding themselves. Max wouldn't ever do anything if she wasn't pushing him all the time.
She regrets it a second later, but it's too late to take the words back. And poor Max, crushed, goes into a deep depression. "I'm useless" he says to himself and anyone else who will listen.
His parents, concerned, shower him with caresses and encouraging words, but this only makes him more nervous. Finally, with some encouragement from wise-beyond-her-years Lili, they realise that just treating him normally is more likely to get results. Max does indeed recover, and works his ass off to show that he can be a star. He never does become first in the class, but he's close enough that he feels he's made his point.
Do big sisters usually look out for their little brothers the way Lili looks out for Max? If so, they must be damn useful!