I thought the tips about calming puppies were awesome! I, too, have worked with dogs a lot, not in fostering, but I have been a groomer and worked for 2 vets. We own two adult dogs who can have some separation anxiety problems when we are away from home on vacations and such.
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My dog had severe separation anxiety when we adopted him. His loving owner doted on him until the husband broke his hip, was taken away by medics in an ambulance and had to move into a nursing home that would not take large dogs.
A friend had picked up this new CD that's out, made just for pet separation anxiety. She said it calmed her dog significantly - plus, she said she really liked the instrumental music as well.