Sorrell and Son by Warwick Deeping

There was good news. The little lady had rallied remarkably during the night and the very eminent surgeon who had been waiting on the threshold of her room for Nature's beckoning finger, went in and laid his succouring hands upon her. Scott, unable to keep still while the operation was in progress, wandered about the garden and in and out of Roland's room. When in the garden he was for ever looking up at the window of his wife's room, for one of the nurses had promised to wave a handkerchief if things seemed to be going well.

Roland, who was writing letters at his desk, found Scott leaning in at his window.