Sick for the first time

We made it nine months but my little guy is sick for the first time. He’s negative for strep and flu but he has a cold on steroids- fever for the last day and a half and his nose has turned into a booger faucet. I know it will pass, but I feel so bad that he’s so sick. What I’m most worried about is that he won’t eat or drink anything expect vanilla ice cream. My mom said if that’s what he wants, to give him that but I’m worried he’s dehydrated. Today he had one jar of baby food, some puffs, some formula, and a bunch of ice cream.

Any tips for getting some fluids into my little guy?