Crybaby (2008)

Piv is in 3rd grade. She is a quiet girl who is often bullied by the quarrelsome Mia and her girlfriends. One evening, Piv's parents have invited one of their old friends to dinner. The friend has taken his daughter with him, who to Piv's horror turns out to be Mia. The parents do not know anything about the girls' stressful relationship with each other and also do not notice anything during the dinner. After dinner, Piv and Mia go for an evening walk in the dark forest, where Piv has previously seen a dead cat in the forest lake. She challenges Mia: Does she, like Piv, dare to walk all the way out of the tree trunk to see the cat?