If Timmy was acting of his own volition and was actually smart, he'd have done his research. He'd know that 8 kids die from gun violence every day and another 32 are injured.
Timmy would've learned that he's three times more likely to die a gun-related death than to drown, he'd also know that after car crashes, it's the leading cause of death in kids.
I think he's just discovered that there have been over 1,316 school shootings since 1970 and he's burying his gun because he's just reflected on the unnecessary devastation they can cause and has realized kids shouldn't have access to them.
CDC, WISQARS https://www.cdc.gov/injury/wisqars/index.html
https://www.thetrace.org/2019/08/children-teens-gun-deaths-data/
https://www.nejm.org/doi/full/10.1056/NEJMsr1804754, N Engl J Med 2018; 379:2468-2475
DOI: 10.1056/NEJMsr1804754