My family has a small hobby farm with a fwe hundred acres of land. We have a 11-year-old Australian shepherd and some toy-size dogs. We recently got a new Australian cattle dog, and boy he is VERY hyper. But if you take your time, he can be trained and behave better. VERY smart dog, although like the shepherd, it'll probably take me a while to train him to play fetch properly.
He helps herd the horses (with the shepherd), usually every day. Does a pretty good job, and loves to chase birds.
[EDIT: I should point out that my family doesn't have any young people (youngest is my brother, who's 19). All of us are more than capable of protecting ourselves from the dogs.]
[EDIT^2: Also, we've never had any of our dogs attack anyone. All of them tend to live very long lives: two died at 16, one at 17, and one at 19. None died younger than 14, although a few ran away before they were 10. Never found out why in any of their cases. We love dogs!
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