Meg, if she has had a pretty bad tummy bug, it could take her a while to even get her appetite back, let alone being able to stomach certain foods again. I know when I was a child, when I got sick, I couldn't stand to eat any of the foods i'd eaten in the day or so previously to getting sick for a long time after the illness had gone. Maybe Tilly is like this? or you could ask her what she really feels like eating at the moment and be content with that for a while and hope that she starts eating her usual diet again soon. I wouldn't worry about being without meat for a little while, I'm sure she has plenty of iron stores etc built up to combat that.