Reply #17: if you don't "know about guns" - DON"T get one.

[mzteris]

And don't get your mother one, either.

Unless you know how to handle one, it's more dangerous to have than not.

Get your mom a bigger dog and your bro some zyrtec. (Or get a dog that's non-allergenic.) Dogs are basically deterrents just because of the noise they make taking away the element of surprise. If someone has targeted your house for a particular reason, they'll have taken the dog into consideration.

Another question would be, WHY would your mom be "a target" anyway? Does she have money? Does she look like she does?

Get some motion detector floods for the front and back of the house. Buy some better deadbolts and window locks. She'd be much better off.