I would go with the Lab, they are great with kids and I disagree with the other poster that said "Barking doesn't stop anything". If the dog is in the house and is barking, then there is a high probability that they are not going to break into the house (Now your car, boat is another question). Just like having a big mean german shepard or pit bull will do no good to protect your house if it is in the garage.
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"A bad day fishing, is always better than a good day of yard work"