Dear Erica,
Had the killer known people in your mom's school may have been armed, chances are he'd have picked another target.
Your pain does not permit you to infringe on my rights, or my choice for how best to protect my family. I'm sorry if this sounds indelicate, but we're months removed now from the mass murder -- already against the law, and your loss from which I truly am sorry for -- so I'm just going to say this to you as plainly as possible: the very fact that so many people were killed under circumstances you wish to see exacerbated means that, frankly, you are one of the last people those of us who wish to keep our families safe ought to be listening to.
Is part of his reply, go read the whole exchange and see just what people should be saying to anyone that tells you that the 2nd amendment isn't needed.