Have you considered the obvious?
You have twelve mixed breed puppies.
I would have already given it peace.
You have homes for all these puppies?
Teach your daughter the responcibilities of raising animals.
My older bitch was bred once by the breeder as a young dog. Two of her puppies had neurologic signs at around 3 weeks of age.
Her puppies were in turn put to sleep.
For the sake of your poor dog. Please have her spayed after this litter. There are low cost spay/neuter clinics out there too.
Get the pup to the vet, for at least an exam....
My gut too says, to let this one go.....
Just my two cents...