Fever can't eat rice? 🤣

Lol my MIL told me don't feed baby rice or porridge when they got fever if not fever will spike. First time heard of it, ive been eating porridge when Im sick, didnt make me any sicker. Anyone heard of this? if not im just gonna fuck it and cook porridgd for my baby cuz hes having stomach flu, want to cook somethong more easily chew and digestable.