My Grandson Stayed With Us This Past Week. Each Evening

My grandson stayed with us this past week. Each evening his stomach began to hurt and he would throw up or feel like he was going to several times throughout the night. The next day he said he felt fine, but when evening would come, he would experience the same condition. At first I thought it might be anxiety from being separated from his parents because he didn't have a fever, but then on Saturday his fever shot up to 103. He didn't have the stomach problems until the evening, but he continued to have a fever through Monday. We treated it with Tylenol as needed. His parents are taking him to the doctor but I have never seen a child experience this type of illness. I am a little suspicious of a possible bug bite or bacteria infection since he likes to play in a wooded area near a little creek. He is six.
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