On a less less pleasant subject, are they eliminating okay? They look young enough that they may still need a little stimulation to urinate and defecate. If they are not eliminating enough, you need to rub a warm rag or paper towel, down near their bottoms, on their belly. Rub in little circles or from rub from the lower tummy down towards their privates in quick little strokes, like their mom would lick them.
Kitten constipation is a very serious problem with kittens removed from their mothers at an early age.
I am currently taking care of some feral kittens here too. They are about eight to nine weeks old and have an upper respiratory illness. I have two of them housed in my dog crate. They don't like me much. Thank goodness they don't need the tummy rubs any more..
I am giving them antibiotics and using a/d prescription diet for them. One of them was severely dehydrated last week, but is much better now.
I have not been able to catch one of the kittens. But he doesn't seem as ill as his siblings.
The older feral cats in the colony.. well.. let's just say they know me.. they run TOWARDS me when I open the door or pull up in the car. A couple of them roll around in front of me and trip me and want to play. They are last years boys.
I need to get them all fixed...