Oh shoot - which one ate chocolate ? was it alot ? If it was just a little...you may be ok...
Go here to read more...
http://www.dogicuts.com/index_files/toxic.htm
and here...
http://www.peteducation.com/article....articleid=2238
Chocolate’s problem ingredients are theobromine and caffeine,
which are rapidly absorbed through the gastrointestinal tract and metabolized in the liver.
White chocolate contains the smallest amounts of caffeine and theobromine, while the concentration of both chemicals increases as one moves to milk chocolate, semisweet chocolate, bittersweet chocolate, and baking chocolate.
The darker the chocolate, the more dangerous it is to dogs. As little as 20 ounces of milk chocolate, or only 2 ounces of baking chocolate, can cause serious problems in a 10-pound dog. Honey weighed 70 pounds, and she died after eating 24 ounces, or slightly less than 1˝ pounds, of semisweet chocolate.
Signs
Common signs include vomiting, diarrhea, panting, hyperactivity, restlessness, ataxia, muscle tremors, increased or decreased heart rate, irregular heart rhythm, increased body temperature. Seizures, coma, or death may occur. Less frequent symptoms include abdominal pain and blood in the urine.