Kitty has very crusty eyes

Someone dropped a little kitten off in a box beside my house yesterday and I of course took her in because I am a sucker for cats. We have eight other cats and none of them have ever had crusty eyes and this poor little kitty can't even open hers unless I rub a warm washcloth over them for a few minutes. She doesn't appear to be more than 4 weeks old. She's very tiny and I gave her kitten formula. I'm going to call my vet in the morning but is there anything else I can do to help her eyes until in the morning?
thanks in advance.

Just keep cleaning them off and make sure she eats.
Is she fairly active? wiggle when you try to clean her eyes and eat well?
If so she should be ok till the vet sees her in the morning.

In the meantime, keep her away from your other cats and thoroughly wash your hands, change any clothing that she comes in contact.

Here try these foods

Innova evo. Orjen. Natures varity raw is also good but talk to sharky she nows ALOT about feine food

The vet was unable to see her today(only open for 4 hours and they were booked full) but I can take her in next week. I do have her in a seperate room from my other two cats. She is fairly active and she's eating good. I cleaned her eyes off last night and when I put her down she saw her shadow and started chasing it. I went and got her a little ball and she played with it for a long time. Thanks you all for her help.