Our 2 Year Old Was Hospitalized For One Day For

Our 2 year old was hospitalized for one day for IV treatments for Rotavirus, 2 weeks ago. She is a 26 week preemie twin and could vaccinated against it because she was in the NICU. Three days ago she starting throwing up and we took her back to the hospital. They treated her with anti-nausea medicine and sent her home, after 8 hours. Since then, her twin and two other family members also starting throwing up. We thought that this was a stomach flu, since we all got it. However, she has quit throwing up, but has been lethargic and sleeping a lot. So, after taking her to the Clinic, her doctor is putting her back in the hospital and said she is not deharated, but close to it. The doctor said this time they are running full blood tests. Also testing for UTI, her blood sugar and even leukemia. We are scared. Could it be leukemia? Could it be Diabetes? Or, could it be a recurrence of the Rotavirus, or stomach flu complications?