What seemingly set the “man” over the edge was that his mom stepped in to take his sister’s side, so he went to another room, doused himself in lighter fluid, came back into the kitchen where lit himself on fire via the stove – in front of the family (that’ll show ’em!).
Paramedics worked to revive the “man” but he died from his burns at the hospital. Reports show that while the “man” did suffer from an unspecified physical disability, there was no mental issues known.
(ed: There is no mention of what brand of cereal the fight started over, but I’d light myself on fire if someone tried to bogart my Lucky Charms and then my own mom even got in the way)