I've made a family with a lovely spaniel, except I must have selected the wrong option and he's turned out aggressive instead of cowardly - he keeps snarling at everyone! I can't even 'Praise for positivity towards others' or whatever it is, as he's just horrible to everyone! What can I do?

If you have SimPE, with the game closed you can go into the dog's character file and change the personality. I've had to scold hostility towards others a few times in the dog that Pascal Curious has. (The dog does the coward trait, but still acts aggressively towards Pascal's kids.)

You can train him to be friendly by scolding hostile behaviour as well as praising friendly behaviour.

This actually makes a bit of sense. Real world sense, that is; I'm not sure it makes sense according to the game's programming. But in real dogs, aggression arises out of fear almost as much as it does out of dominance. I've got a pack of seven, and a couple of them are rescue dogs, both purebred pit bulls taken from people who bred dogs for fighting. Until they settled in and learned their places in our pack, they were the most aggressive dogs I've ever had, but I could tell that it came from fear, from a feeling of having to protect themselves. The attitude is all different from a dog that's aggressive out of dominance. NOW the two of them are the most laid-back dogs on Earth, but it took a while. So a "cowardly" dog is often MORE aggressive than one that is securely dominant. In the real world, like I said. It's probably not to be that way in the game, though.

Just a normal self defense mode, dogs or humans....sims? naw. lol