heh, this is funny. I dont know if you're either channeling him somehow because you like the same stuff as he does or you have been directly influenced by SplatPixel, but it's defintively reminiscent.
http://pixeljoint.com/pixelart/12647.htmHe's an old user of pixelation, he always did these light skinned doll-like characters. I'm not blaming you of copying or anything like that though, this monster is clearly your own, it's far fatter than anything I remember him doing and I dont think crotch faces or shoulder stingers were something he was into either :p it's just kinda nostalgic to me to see this light skinned doll character, thought you'd dig hearing about splat's work regardless of wether you knew him or not, since it has some similar tastes.
I made a quick search for sickly chicken and by reverse image searching the sickest chicken I saw google suggested "raw whole chicken" as keyword, which yielded this among other things

one big, easy to replicate feature I see is very very pale beige skin, with almost no contents of orange (makes it look alive and healthy), and patches of purple or reddish pink discoloration. Anything more would be simply adding sagging skin, subsurface traslucency like Gil said and other sickly looking features, but that sounds far more complicated, so if I were you I'd go for the easy thing first and then judge how much more I would get from more work intensive detail