Griffin's Colds

Griffin's colds just started again just when I thought his colds were going away. I wonder what's wrong with him. It seems that everytime he's getting better, he gets colds again. It might be allergy since this has been going on for 4 weeks already. My poor baby, I hope his colds go away for good. I don't want him to miss school anymore since they only have a few weeks left before summer vacation.