Aggressive Licking Dog

Question
QUESTION: We've got a new baby.  When my mom visits with her aggressive dog he stares and licks his chops when the baby cries.  We are being very cautious but are curious what this behavior means and if it is a sign of aggression.

ANSWER: Hi, Chell,

Please tell me first why you consider your mom's dog to be aggressive.  What have you seen or what do you know about his behavior?

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QUESTION: Shep barks and lunges at most people and pets, without any provacation. When he's confined he destroys anything within his kennel or room. We are not fearful of him but many others are. He has limited, supervised exposure to the baby. When the baby cries Shep wants to be very close and licks his lips (like a tiger when he sees a piece of meat).  We believe its just anxiety but are wanting to know the true meaning behind it.

Answer
Hi, Chell,

Most lip-licking that a dog does is done when they are stressed.  Your feeling that it is anxiety is probably pretty well on the mark, especially if you stay Shep does it when the baby cries.

That sound could be very disturbing to him, especially if he's never heard a baby cry before.

I think you're doing the correct thing by only allowing supervised exposure to the baby.  I don't think he has the same interest as a "tiger eyeing a piece of meat," as you put it, but his size and curiosity toward the baby make him an unintentional threat.