Educate Educate Educate! make sure they know what it is and what it can do. The best thing you can do is teach them gun safety. With that out of the way, IMO a gun with nothing in the chamber is a paper weight. If your wife is gonna need it, shes gonna need it now, i'm sure she will be shaking enough if a situation arrises, the less things she needs to do to make the gun go bang the better...
+1 Very well said. These would have been very close to what I would have siad, but I will refrain since you already did.