AURORA, Mo.—Kari Boettler could not comprehend what she found on her late son’s cellphone on Feb. 5, 2024. She was searching the metadata to determine why 16-year-old Evan had shot himself in their backyard that January.

Sitting on the sofa in the same living room in which Evan had just celebrated Christmas with his family, only feet from the spot where he died, Boettler tried to make sense of the explicit photos and threatening text messages she found on Evan’s smartphone.