Yeah, that can be a tough thing to teach a little dog. It's a defense mechanism. I've had some luck teaching them to "speak" on command first so they know what it is, then teaching "no bark." Eddie now loves the no bark trick because he doesn't have to do anything to get a treat.
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Mike ~ Doting Dad to Jillie, Harper, Molly, Cooper, Eddie (RIP), Lucy (RIP), Rusty (RIP) and Jack (RIP).
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