Another bug...?

Dear Nicky,

You arrived home in fine spirits this afternoon, but when dinner came, you tried to climb into your seat, and when I looked away for a second, you fell down and cried. That's when I noticed you felt hot. You ate nothing and barely drank anything. I gave you some mess and put you to bed early. When I checked you a little while ago, you seemed sweaty but cooler. I hope this bug passes quickly.

Love,
Dad