Many tranny kids are indoctrinated by their parents, especially their mothers. The corrupted degenerate globalist controlled society can also play a huge role. Keep in mind that a lot of Western people spend most of their time online, in echo chambers, which can cause brainwashing all on their own. From the stories coming out about this shooting, it looks like the mom was likely responsible, as she was an avid anti-gunner. Most lefty NPCs parrot the mainstream media verbatim, so she also likely kowtows the LGBTQ tranny programming too.