When I was concerned about my friends in each nation kat told me about how you could set a little memo for each friend so you could remember what nation they're all in.
That was a bit time consuming so I remembered a really useful function that I forgot since... level 20 or so.
Make groups!!!
so much easier than memos
feel free to not reply... I personally felt like an idiot to forget.
If you aren't in my list... it's cause you didn't ask...