Keep a watch on your grump's body temp and general behavior including appetite. Leaving puppies like that is not normal. Most of the time you have to drag the girls away, so she may not be feeling well in some way.
I keep a temperature log on my girls for at least 7 days post whelping to make sure I catch anything going on (such as uterine infection from retained placenta or other, mastitis) as early as possible.
Anything over 102, see your vet, and I am calling if it goes above 101.5
Good luck, they are really adorable!