Replacement food for kittens that are still nursing?

Give the mother her food slowly or if she seems really hungry or something. The kittens can drink from the mother but she'll be drained faster and since you don't have a lot of food I would give the kittens and the mom milk. If you have one of those nursing bottles for cats or a syringe you can give it to them like that but they should be able to drink from the bowl on their own. Good luck!