"i have a friend who had a miscarriage and is reassured she will meet up with that baby in heaven but it just seems very starnge to me - she doesn't even know if she'll be looking for a boy or girl"
With what does she imagine she'll be meeting?
You don't say at what point the miscarriage occurred, so it could have been anything from a few cells to a foetus, but either way, there wouldn't be anything of a personality (unless, I suppose, it was a very late miscarriage and you can characterise 'used to wriggle when I played AC/DC records' as a personality).
It's just such a nonsense.
I understand miscarriage is frequently very traumatic, but to think that there could be anything to interact with is obviously daft.