Starangelk, i would second the fruits and eggs. DD will eat her favourite things if anything at all when she's feeling sick - for us that's cruskits with avo, buttered toast, slices of cheese, scrambled eggs, sour cream (obsessively!), pasta, sometimes yoghurt too. She's been been put off corn fritters twice now by eating them when she's sick though.

Like a PP said, water is the main thing. DD will often eat barely anything for a week while she's sick.

Hope your lo is feeling better soon!