Have you ever thought this kid must be bewitched? It was a common concern long ago, that and being struck with evil eye.
To determine whether a child had been inflicted with either three Oak apples were cut from the oak. Oak apples were galls created by the larva of a particular wasp.
After cutting the Oak apples from the tree, they were dropped into a large bucket or pail full of water and placed under the child’s cradle. If they floated, all was good, but if they sank, the child was bewitched.
This had to be done in absolute silence to get accurate results.
You can read more about Oak Apples I got images here too.