Most all dogs will get along well with children if they are raised with them. However, some breeds have a protective streak in them and may become aggressive with children who get to close at meal time (although this should not be tolerated), or aggressive with children they have never met. These breeds will likely see the children as being underneath themselves in the "pack order" and may try to dominate them.
Keep in mind that large dogs are more expensive to keep. They eat more food, which costs you more money. Tick and flea preventives cost more for large dogs, as do other mediations.
Dogs with short coats also have another advantage. It is easier to find ticks and fleas on their body. You probably spend eight times as long searching for fleas and ticks on a dog with a long coat than you do on a dog with a short coat.
Some dogs will patiently put up with little children who pull their ears or accidentally poke them in the eyes, while others will not and map nip or bite back in defense. So if you want a dog who is excellent with children avoid breeds which may have a dominance streak or that have short tempers.
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