Aimesmum I am veggie, my kids are not and I have ALWAYS told them where there meat comes form. It is dead animal, they HAVE been killed so they can eat meat. BUT if people didn't eat meat there would be no fluffy lambs in the fields and cows in teh meadows. I truely believe we should let our children see what animals are bred for and explain to them as SW says. Like I say my kids are not veggie, although I am. They would have the choice o be veggie if they want.
If she wants to stop eating meat as DD1 is seeming to do, you can use quorn at this age, also beans on toast is a good meal, along with eggs, cheese etc. I suppose it depends how you cook. DD1 will now only eat the odd bit of chicken when she fancies it, and sometimes sausages, although she still lovess fish.
Please don't make it an issue if you can help it !!