Awwww...what a good little sweetie. I don't think you're missing anything here...I just think you have an innately secure little pup. Some puppies are just that way...calm, secure, no separation anxiety. It's probably just her personality...and you're lucky
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When my dogs were pups, I'd always make sure they had a stuffed "Momma Dog" in their Iris pen/gate -- ie, a stuffed dog about the size of their Momma. Maybe yours would like that too...?
Btw, pics please
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