24 hours and mallard hatchling still won't pick up his head

[sjaksec]

this guy was assisted out about 24 hours ago and looked pretty good. spent all day on his side, but active. noticed he had a big umbilical last night that looks like a dark smaller mass now. ive been able to get drops of nutrients into him, and he's fluffed out and good size, but he's still on his side and cant lift his head. anyone seen this before? If I can keep the fluids going in, might he make it? I havent seen him poop yet, and wondering if that big umbilical may be representive of a problem. the space on his abdomen appears to be a bit of an opening last night that is smaller this morning and looks almost normal. he's peeping and moving his wings. just cant get off his side/back. any ideas would be greatly appreciated. 4 eggs, only one made it so far and he's healthy and growing. these are abandoned mallard eggs and the healthy guy sure could use a buddy to hang with.