The art of damage control

The Doctor's satisfied smile froze, his hearts missed several beats.
Two children were gaping over his shoulder in terror, witnessing carnage no ten-year-old ever should.
"I have a story," he improvised quickly. "About sour grapes and sweet berries."
He talked and gestured, accompanied by his spoons. Soon the children forgot their terror.
"The sour defeated the sweet." he ended.
"So should you, candy isn't healthy."
"Was the story true?" A child asked.
"Maybe."
"Were you the grape?"
"Who knows," he replied, winking.
Both children laughed and unwrapped a lollipop.
"Well, you can't win them all," the Doctor muttered and smiled.