Can she defend herself?

Early in our courtship I found my wife could defend herself. She studied a little Kung Fu, which helped, but more importantly she knew to stand up for herself, was aware of her surroundings, and was (and is) self confident. Sometimes she doesn't know when to back down (remind me to tell the tale of the drunk who was urinating in the bushes), but I normally feel confident she can protect herself. Oh yeah, she is also a better shot than I am.

Having firearms required some serious thought on our part. Having a gun in the house means that you may use it - sounds obvious, I know, but if you are required to use that firearm, you will likely injure or kill someone. One must know that in advance, accept it, know the ramifications it will bring, and pray that you will never need to use it.
Having a firearm for self defense and having children in the house adds another dimension entirely. The firearm is for self defense - in other words, it is a safety issue - but the children need to be protected from the possibility of injury due to misuse - in other words (again), their own curiosity.
One tool is the Eddie Eagle program that the NRA sponsors. It is a good starting point. Another tool is the dulling of the child's curiosity - if the weapon is not a mystery, and the child can handle it (with supervision, after the weapon has been rendered inoperative), then curiosity is lessened, as is the chance that the child will gravitate toward the weapon unsupervised. I've also taken the girls to an outdoor range - not so they could fire the weapon, but so they could hear the noise (with ear protection, of course) and see how destructive a bullet can be.
I would recommend Cornered Cat as a web site worthy of note for anyone, but especially women who may be considering (or already have) a firearm for self protection. My daughters will study the information here when they reach the right age.