At least 157 people were killed and 270 were injured last year in unintentional shootings by children, according to Everytown, an advocacy group for firearm safety.
Historically the 2nd amendment was never a personal amendment like the 1st but a states rights amendment like the 10th amendment. Eg the feds cannot disarm lawful state militias.
This kind of oversimplification leaves out how corporate gun manufacturers have embarked on a decades long venture to reinterpret the 2nd amendment to basically be "you have a god given right to sell guns" and the republican policy here is simply the current pro-corporate policy. If corporations shift on this republican politicians will as well (and they have, people forget Ronald Reagan introduced gun control)