[Kaderin Triste]

The basic summary of the book is that kom and dad are too busy taking care of the older and younger sibling to pay attention to the middle kid so the middle kid makes messes and is noisy in an attempt to also be given attention, but just gets shushed. So then the m.k. hides in a closet and pretends to run away and the parents panic a bit until the m.k. crashes out of their hiding place.
But it basically sums up perfectly the feeling of being ignored and being made to feel unimportant because the parents are busy fawning over the first-born and the baby.