JUST "CONCERNED PARENTS":

Four days before the shooting, Ethan accompanied his father to a gun shop, where James Crumbley bought a 9mm handgun, prosecutors said.

Ethan posted photos of the gun on social media, writing, "Just got my new beauty today." The next day his mother posted that the two of them were "testing out his new Christmas present," Oakland County Prosecutor Karen McDonald said.

McDonald detailed a number of other warning signs that she said the parents failed to act on.

On Nov. 21, a teacher found Ethan Crumbley searching for ammunition on his phone. His mother later texted him, "LOL, I'm not mad at you. You have to learn not to get caught."

On the morning of the shooting, a teacher discovered drawings by Ethan Crumbley that depicted a handgun, a bullet, and a bleeding figure next to the words "Blood everywhere," "My life is useless," and "The thoughts won't stop - help me."

School officials summoned the Crumbleys and instructed them to get Ethan into counseling within 48 hours, McDonald said. The parents "resisted" the idea of taking their son home from school and did not search his backpack nor ask him about the gun, she said.

After the Crumbleys left the meeting without their son, Ethan Crumbley was returned to class and later walked out of a bathroom with the gun, killing four students and injuring seven other people, authorities said.

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