C.S.
I have heard of that same thing happening when the child has an allergy. I don't know why it would just start now, though, unless her diet has changed. When my husband was a baby, my MIL would find the same mess every single morning - found out it was a milk allergy.
When my son was around 10 months old, he had the same symptoms for about a week and then it cleared up. Pediatrician said his was just a harmless virus and we'd have to keep him hydrated and just ride it out. She was right.