When our daughter was young we had a lab shepherd cross from a rescue society. Great dog, and it was unfortunate we could not give her what she needed. She ended up in London on a horse farm, so it worked out. One day my daughter was playing in our front yard while the wife and I were doing the gardens. Charlotte (the dog) was lazing on the lawn. A neighbour walked by and as soon as his Rottie came into view, Charlotte perked up. Wife made noises to calm her down, but I told her to let it be. Rottie looked at our daughter, and I guess Charlotte did not like the way he did it because she let out a low growl and a single loud bark. The bark we knew, but the growl was something very different. Never heard it again from her. The Rottie literally jumped behind it's owner and started to whine. God, it's been over 10 years, and I am sure that Charlotte is no longer playing with the horses but I loved that moment.