After some thinking... ;p... i do believe Lucina is Nia because after marrying kiho, with tilly gone, she become the king mother. But maybe im wrong. Anyhow cant wait for the truth to reveal or the first life after tilly die is reveal.
heck that was more like a tea party where girls use their tongues like swords to "stab" the other person. Dont u have better things to do UR ROYAL HIGHNESS ;) cuz if u dont...............