Possible ways for a character to die?

she witnessed a murder. the killers found out she saw them and threaten her with her life. she still decides to go to the police. the police offer her protection if she helps them but only until the killers are caught. the killers get caught but this made the people that hired the killers angry and they want her dead. this girl is smart and very organised and babysits on weekends not the type of girl who gets involved with drugs or violent people. The other idea i have is that the girl mum is a social worker. she seperated a women from her husband because the husband was too violent. "the husband" is now threatening to kill both her, her mother and little brother. they've moved to three new towns in two months but every time "the husband" finds them and they have to move again. hope that helps!