My daughter was diagnosed at the hospital with chicken pox- could this be hand foot and mouth disease?

Viral infection: Hand/foot/mouth disease is a viral illness usually caused by a virus called coxsackie virus. The body will usually fight this off on its own. Insure plenty of rest and fluids. The illness spreads by person-to-person contact through nasal secretions or throat discharge, saliva, fluid from blisters, stool, and respiratory droplets sprayed into the air after a cough or sneeze. Wash your hands!

Location of rash: Both diseases are caused by viruses, but hand foot and mouth disease is limited to those areas. Chicken pox usually begins in the head and works its way down the body.

Some similarities: The blisters are similar & early disease on in either they could be mistaken for one another. After a few days the distribution and cycle of blistering would make it easier to separate the two. I can see where a single observation early in the disease may not lead to an accurate labeling.