He's the little one you posted photos of a bit back right? What and how is he eating now? Have you tried hand feeding him if you are willing? You might not have to do it forever, but Doc seemed to need it for a week or so. I fed him 3-4 times a day, basically as frequently as I could manage. From a syringe that I had left over from various vet visits. He ate just a couple ccs at first, we worked up to him taking 5 or more. He was probably about 2-3 weeks at the time. I think the yogurt really helped the consistency of the mix to be nice and smooth.