8 year old yellow Lab. 121 lbs from really big English purebred parents!!!
Won't let any strange adult person into our house, if we're are not home. I've had friends drop by to pick up stuff with my permission while I'm not there and it didn't go well (no biting, just a lot of teeth, barking and growling).
But, when he is at the playground and a small child approaches (even babies) he sits down and let's them pet him and loves the attention, will drop his ball at their feet and when they throw the ball, he brings it back to do it all over again. If another dog approaches the child he will get very protective of the child and growl and chase the dog away.