petulancy
/ˌpɛtʃuːˈlænsi/Definitions
1. noun
Peevish or sulky behavior, especially in a child.
“The teacher tried to address the petulancy of the student, but it only seemed to make things worse.”
2. noun
The quality or state of being petulant.
“The petulancy of the child was starting to get on the nerves of the parents.”