"Stephen remained as always, though barely consciously, on the watch for children, for a five year old girl. It was more than a habit, for a habit could be broken. It was a deep disposition, the outline experienced had stencilled on character.
It was not principally a search, though it had once been an obsessive hunt, for a long time too. Two years on, only vestiges of that remained; now it was a longing, a dry hunger.
There was a biological clock, dispassionate in its unstoppability, which made his daughter carry on growing, extended and complicated her simple vocabulary, made her stronger, her movements surer... she would be drawing, she would be starting to read, she would be losing a milk tooth. She would be familiar, taken for granted.
It seemed as though the proliferating instances might wear down the frail, semi-opaque screen whose tissues of time and chance separated her from him...
Any five year old girl - though boys would do - gave substance to her continued existence. He could not fail to watch out for Kate in other children or fail to feel the untapped potency of weeks and months, the time that should have been hers. Kate's phantom growth, the product of an obsessive sorrow, was not only inevitable , but necessary. Without the fantasy of her continued existence, he was lost. Time would stop.
He was the father of an invisible child."
Ian Mc Ewan, The Child in Time