Same is true with us. We have labradors outside. Two field trial dogs are kenneled out by the shop and the other is just a pet that sleeps on the back deck. There is nothing that gets by the dogs, even the kenneled labs. If the wind blows, they bark.....if another animal ventures near the house, they bark. But when a person, friend or foe, comes near, they practically go nuts. There is no doubt in our mind when someone is around. They actually bark differently when it is a possible threat rather than a " I want to get the rabbit" bark.
It has been hard to deal with our inside dog, a yorkie, knowing she is growing old. Nothing used to get by her either. But as she has reached 15, we can come home, shower, watch tv, etc. and she sometimes never knows, and she is asleep as we step over her for hours. So that security is gone, but it will be a tragedy when she leaves us.
I am sorry for your loss of family member, it is a day I have worried about for years when our yorkie goes to doggy heaven.