I have found with our 3 chihuahuas that although all three are sweet, Ricky (the male) is more protective of me and so I have to be careful when strangers approach me suddenly. He doesn't bite but he will do his "warning" growl.
On another note: My male was easier to potty train and has never had an accident in our home or motorhome whereas my females are more likely to go in the house if they aren't taken out immediately. I have spoken to many people who say that their females are also more likely to have an accident in the house.
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