Grand Duke Henri received in audience Mr. Raoni Metuktire, today 20 May as part of his European tour
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Grand Duke Henri is attending the 16th Informal Meeting of Heads of State of the German-Speaking Countries in Linz, Austria.
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She attended in the past so not speaking german can't be the reason.The Grand Duchess was missing at the Head of State for german speaking Countries.
Perhaps because she does not speak german or she was in Paris.