A 16-year-old girl became a suspect in a criminal case of 4 deaths. How did this happen?

On 24th 19: 30, a major criminal case occurred in Zhu Fang Township, Nankang District. After the victim Xiao was killed, the police arrived at the scene at the first time. Through investigation, it was found that there were two murderers, one was 43 years old and the other was 16 years old. The reason is that Hua and his family are looking for Xiao Mouying's home? Theory? There was a fierce quarrel. Hua took out a firewood knife from home and chopped it at Xiao Mouying (46 years old), Ting (14 years old) and Long (10 years old) with a kitchen knife.