No, if the kitten is that old, it can probably use a little box (if its 4 weeks).
EDIT: Make sure she doesnt eat the litter, as kittens like to do.
And eye droppers wont work all too well. Go to petsmart and buy a kitten bottle. Make sure the hole you make in the nipple is big enough to wear if you apply pressue, milk drips out fairly easily. Use Kitten KMR, as its the best milk replacer you can get. But at 4 weeks try softening dry food with the mixed up KMR, or trying a little KMR second step gruel. Make sure no to use purina kitten food, as it make my kittens ill. Watch our for any blood in the stool, ovious disconfort, or painfully bloated bellies as this can mean worms worms worms. If you kitten constantally throws up its food, bring it to the vet and ask him to look for stomach worms, as this will kill kitty quick. You dont need a heat lamp or heating pad at this age, just be sure that no vents are blowing on kitty and that its kept in a all around wire cage is pently of bedding and a shallow water dish that hangs from the side of the cage. You may also want to try putting in some dry food at all times. Also make sure kitty has plenty of supervised excersize time as well though. Watch kittys eyes, becasue if they seem sunken in and you can see part of the extra eyelid thing, that means shes dehydrated, so get milk in her fast, just dont EVER use cows milk. If the kitten isnt going potty, stimulate her too by rubbing her behind SOFTLY with moist paper towels. Make sure she goes # 2 often or you have a probelm. Take her to the vet if diareah occours often, but dont be alarmed by soft stools. If she survives, which it sounds like she may not, sadly, she will probably have metal problems from growing up with out other cats. She will probably be a biter, not having a mom to keep her in line and siblings to show her biting hurts. Nothing really helps this, not acting like a mom cat, not anything. Iv tried it all. Anyways, you can email me any specific questions you have if you like as well. Sorry that jumbled up, but hope it helps!