My Dog Had 4 Puppies 10 Days Ago One Of Them Die Yesterday And Today One Of The 3 Left Was Crying ..i Pick It Up And Hold It Close To My Chest And Rock It A Lil And He Poop Could It Be That He Couldnt Poop Right? He Didnt Want To Eat B4 Now He Do.

You need to consult your vet. Everything checked out okay at the time of your post whelp exam (24 hours after whelp) and if you had dew claws removed or tail docked and the initial puppy check (2 to 5 days)? Vet said everyone looked pretty good so far? That helps eliminate some of the options as to what could be wrong usually. Crying fussy pups at that age isn't normal and means there is something wrong. They are hungry, or cold, or sick, or in pain. They just sleep, eat and get stimulated pretty much and are quiet other than nursing and stimulation.
At that age they are stimulated to go potty, the dam will lick them (or if there is a person involved they need to do so) and that causes them to go and usually she eats it. It is possible he had to go and was uncomfortable but with one puppy down (they may be beginning to fade) you want to make sure there isn't a problem with the Dam making them sick, the environment, or that they aren't sick with some bacteria or something. You can lose everyone, including her if she has some sort of infection that is now making them ill very quickly. You want to make sure he didn't potty on you because of an illness or something else and they aren't in the process of dying one by one, what is going on indicates you may have a big problem somewhere and may be an easier fix or could be a serious issue, there is no way to know until you know what may be going on.  
You need to talk to your vet. Never hesitate to call when breeding and whelping the second you think or something begins to go wrong or there is any question about anything (and the vet is used to it), ever really but this is something we choose to do 100% and got them and ourselves into willingly and knowing it meant life and death and just about everything after could be life and death and a lot of vet bills. :-) Hope there isn't anything seriously wrong and everyone is okay.
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