Radar was the "defender." I trained him to defend the house, the wife and the kids. He took his job so much to heart that when my wife and I would "play" he'd bite me because he was "protecting the mommy..." seriously, I have bit mark scars on my legs and ankles from where he'd bite me! Once, may years ago, when our eldest daughter decided that she'd pick a fist fight with Cheri, (and C and our daughter were wrestling on the ground...I had to grab him keep him from attacking our daughter...because he "was protecting the mommy").I miss him now...
He was a great dog, and did what I taught him to do...protect my family and home at all costs (he deterred at least 2 burglaries that I know of)...putting him down today was saddened me far beyond what I would ever have thought it would.
UPDATE: Here's a picture of Radar & Reilly, our other beagle in better days...