My 2 year daughter yesterday passed pale yellow stool. She is not eating much since 1 day and a day before she had loose motions twice.?

Stomach virus. Sounds like she's got a bit of a stomach virus, causing a bit of stomach upset, changing the bacteria in the gut. There can be change to the chemical composition of the stool causing color change. Sometimes that's all that happens, and that's ok. However, the diarrhea can worsen, or fever and vomiting can occur. A probiotic can help get the balance of bacteria in the gut back to normal.