Dear friend,
Check the bag because somtimes a little mold can form on the bottom in this weather. Next check your boys mouth and tongue for any bad teeth, sores, non food items like thread, tstring, etc.The green liquid is bile and it means his stomach is empty. Do not try to feed him any more of that food . If you have a brand new bag - open that and see if he can eat it with no problem, You can also boil some chicken or fish and try that. Give him some plain pedialyte.
In a four year old vomiting can be caused by inpacted hair or stool, non food item, digestive upset, pancreatitis, upper respiratory or sinus or other infection. If you cannot get him to keep anything down it is advisable to have him seen so you can see what is going on with him.
Please let me know how he is and if you have more questions -, I am happy to help in any way possible.
Very sincerely,
Terri
Edited by purrfectkitty on August 1 2006 at 9:32 PM
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Please press ACCEPT if my answer was helpful and leave feedback Thank you! Terri