Shadow the Sentinel

This morning my sister, who is here for a short visit, wanted to go running. She's training for a half marathon next month. We took her and her dog, Bele, and my two dogs, Shadow and Dr. Watson, to the school so Erin could run the track with the dogs and I could watch Emery and cheer her on. I was very pleased and surprised at Shadow's behavior.
We let the dogs off their leashes when we got there, there being no one else around. They began running with Erin around the track and racing each other through the field in the middle. Emery and I started running around in the middle of the track also. I noticed that periodically Shadow would break from the other dogs and run up to check on us. He has done this before and I find it quite endearing.
After awhile Emery started getting bored just running around so I went back to the car to get my key to get in my classroom and find some balls for her to play with. She walked with me to the car and then to the classroom but she was preoccupied with the shiny locks on the lockers so I went in the classroom by myself, got the balls, went out the back door of the classroom and deposited the balls on the field. When I came back I didn't see Emery anywhere. I had that brief moment of panic thinking the worst. It didn't take long for me to find her and when I did there was Shadow standing right beside her guarding her till I got back. When I picked her up he looked up at me and gave a low questioning whine which I interpreted to mean, "Now you have her, and she is safe. Can I please go run with the other dogs again?" So I told him he could go and gave a wave of my hand and he was off racing with the other dogs again.
Later, a man came to run on the track for a little while. Shadow is afraid of people he doesn't know and in the past he has always cowered in fear. But today, although he was clearly still afraid, he made sure that every time the man came around to where Emery and I were playing he was standing between us and the man. He was cowering in fear still, but he was standing his ground.
It makes me feel good to know that our dog is so protective of Emery and me. I don't know how he would fare if he felt that we were actually being attacked, but I have a feeling that his protective instinct would win out over his fear. And that makes me feel slightly better.
Good dog Shadow! Good dog!