I don't know if it's possible to traumatize people by showing them pictures, but it seems like it would be, so it may be wise to delay some things for, say, college or highschool.
As evidence, I present this photograph, captioned: "A Congolese man looking at the severed hand and foot of his five-year-old daughter who was killed, and allegedly cannibalized, by the members of Anglo-Belgian India Rubber Company militia."