Hi, advice needed please

Just to bring you up to date-- early january i got a beautiful little puppy from a breeder, but she was incredibly sick and i had to return her 4 days later as she almost didnt make it through one night. Doing my homework i think that my little lily had liver problems, and the breeder has another litter almost ready and im worried that my next puppy could have inherited something?
Lily was excessivly shakey, wouldnt eat and had dhiarrohea but most of all was extremely lethargic. Unfortunately lots of these things homesick puppies also have.
So this weekend, im going to pick my new furbaby from a litter that is 8weeks old, and i really need advice on how a healthy pup should be acting at 8weeks??
Many thanks
