Very weak, vomiting yellow, can't hold anything in their stomach. Thick slober or phlem, when given medicine hard to open jaw. Before I could do anything one of my dogs died in less then 24 hours. I gave them rebound, nutricare(some kind of vitamins, pedialyte for fever, penecillin with B12 and that got them well. I was devestated for the loss of my pup because I didn't even notice she was sick.

It could be tetanus. It takes about 2 weeks for it to develop from a wound (like from an infection through the navel if it was not cleaned when the umbilical cord was cut)
It could be rabies - if its still a pup, it could have been born from a rabid dam and it would take about 3 months for it to manifest in the pups. Is the dam still alive? If the dam mysteriously died around 2 weeks from whelping, your pups could be rabid and you would be in grave danger because you've been exposed to the saliva. If this is the case, seek medical help ASAP.
If several pups were affected, then it looks infectious - it would most likely be Canine Distemper Virus infection. Its viral and it hits pups that were'nt vaccinated. The virus attacks the gut and brain so you would expect digestive and nervous disorders.
If it is CDV infection, best thing to do is to take it to a vet hospital because it will need intravenous fluid replacement therapy - PEDIALYTE WILL ONLY DO MORE HARM. The gut will most likely be inflamed from the CDV infection and Pedialyte will only act as an irritant. It will also need medications to counteract inflammatory processes in your dog's brain and gut cells. Prognosis for CDV infections is not so good (sorry to tell you) so it is best to have your pups and the dam vaccinated at the recommended intervals.

Could be parvo- it can kill in 24-48 hrs. Need a vet ASAP- I would NOT just try home remedies.

it could be a stomach virus,or distemper...take it to the vet..

A number of diseases or poisoning can cause these symptoms.
If you want your animals to survive seek immediate veterinary care. They need intravenous treatment asap.

Could be a lot of things, but if you have a young pup, it could be parvo, a very deadly disease. Pups need their first shots a t 8wks. If you want her to live, take her to the vet asap!

Canine Parvovirus-2
Symptoms: Severe bloody diarrhea, vomiting, loss of appetite, depression, & high fever. Infected pups may act depressed, collapse, gasping for breath, & death may follow immediately.
Giardia
Parasite
A waterborne protozoa parasite found in pounds, puddles, swimming pools and in the backyard. Giardia is transmitted to other animals by feces. Causes gastrointestinal problems in dogs. Symptoms can include diarrhea, weight loss, abdominal pain and vomiting.