The most likely cause is allergic conjunctivitis which develops along with cold,the child blinks because it feels better while doing so.
The next probable can be if she has any refractive errors,which requires dilated refraction at this age.
Next Steps
Consult online/ offline to rule out other causes.
Health Tips
To avoid allergic reactions follow some of the simple rules:
1. Frequent handwash as possible, especially after playing outside.
2. Apply cold compresses over the eyes to get relief of itching/ blinking.
3. To avoid rubbing of eyes as it can increase the reaction.