I don't think its too early to be thinking about it,definitely sensible to go over it now!
Personally,I don't agree with not letting children know where meat comes from but thats just me.
Maybe you could say something like 'This is really important to me,if I research how to do this properly so the baby is getting all the nutrients it needs and I learn how to cook everything,can we give this a go'?
I'm not going to lie to you,giving small children all the nutrients they need within a veggie diet,if you can't cook,is not going to be easy.But you have lots and lots of time to learn!
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