It seemed at first she was being awakened by a sharp dart, one of those darts of apprehension seemed shot into her approaching slumber.

But it was nothing more than Wayne whistling out on the porch, whistling the dreaming waltz which would bear one to the love waiting at the heart of the night.
But Katie was sleepy now.

How did Wayne expect any one to go to sleep, she thought crossly, whistling at that time of night.
But across the hall was another girl who listened.

She had not been asleep.

She had been lying there looking out into the night, very wide awake.