According to history given seems like Vernal or Allergic Conjunctivitis. It's a common condition which mostly flare up in summers. It's seasonal and can trouble periodically but mostly as the age progresses the allergy goes down. Right now it's better to give cold compress to the eyes.Give cold compress 3 times a day, can dip clean cotton in refrigerator cool water and place it over eyes for 30 seconds.
Next Steps
Looking at the age it's better to examine physically and then start with treatment.
Health Tips
Avoid rubbing of the eyes. For such condition the first line treatment is certain anti allergic eyedrops.