Hi Raelene, welcome to TDK! Go to the grocery and get some goat’s milk, it’s much cheaper than KMR and you won’t have constipation problems with it. You can find it in the cold milk section of the grocery or in the baking aisle in cans. The canned is condensed so just add water 1 to 1.
I am going to post some links for you too on the general care of hand rearing kittens. So sorry you have lost the other baby kittens. You might want to get some wet food also, the pate type, no shreds or chunks. She might be old enough to want to begin to taste it. Just a little dab on your finger, let her sniff it and then put it on the roof of her mouth. I am also including a link on the *triangle method* of pooping a kitten. Take a look at these links, they are loaded with information for you. Keep us posted!
http://messybeast.com/handrear.htm
http://www.safehavenforcats.com/newborn.htm
Helping a kitten to eliminate
.