More seriously, there is a tradition of new avatars joining the House of their character's "parent" (most current family members came up via adoptions). However, I'm not sure there's any rule requiring or even suggesting it has to happen, and Austria has been getting rather big.
Right now I'm not sure Lothar Zirn has any official status, except as owner of Marseilles. If he wins this upcoming battle and the Emperor is in a mood to parley that could chance. You have a rather large (mostly in avatars, not in land) Austria in the southeast. Note the Turks have a human player so that's a dangerous region. In the north the Margrave and his heir (the latter an Austrian transplant). I suspect by the next Diet or so there will be a third duchy, maybe based around Lothar if he wins, or someone else otherwise. The emperor has expressed the desire to bring back Bavaria.
Although the game can't continue until the pvp battle is resolved (and the gm is setting up an event for it) there's nothing really stopping us from continuing to roleplay. I think we've just been waiting to see what happens.
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