We had a Chow-German Shepard mix. She was our guard dog. She seemed to have a good sense of what to do when. She was very protective of the family and would not hesitated to bite if necessary.
Also had a Newfoundland. Dumb as a post but sweet as could be. They were a good team. Ya know, I’m not even sure our Newfie knew his name.
I was in the Columbus Ohio Holiday Inn near the pool a couple of decades back when a kid in the pool [girl, maybe eight years old] started yelling and screaming, aplashing her hands in the water. I wasn't in the way of the dog, but was in line with it. A poolside table with umbrella and four chairs WAS in line, and went flying, as a big black ball headed for the tool in a flash like a torpedo toward a ship. The dog took a leap from the edge of the pool and was alongside the kid in maybe two seconds, and gave her a big black furry pillow to hang onto, and doggie-paddled [how else?] the two of them back over to the edge of the pool.
Turned out the kid had eaten a chocolate Easter bunny whole, choked on it, and gotten a snootful of water in the process, followed by screaming 8-year-old panic.
Good dogs. Good dog, in particular; I would not be surprised a bit if that girl-kid is a mom now, and her kids have a big black lovable fuzzball Newfie as a member of their family, too. And I'm betting your Newf knew his name when he/she heard it from you.