The Grand Ducal Family of Luxembourg consists of the extended family of the sovereign Grand Duke.
The current royal family of Luxembourg consists of the reigning grand duke, Henri, his wife Maria Teresa, their children: Guillaume, Félix, Louis, Alexandra and Sébastien, and Grand Duke Jean, the father of the reigning grand duke, who abdicated in 2000 and still holds the title of Grand Duke.
The family is completed by Princess Tessy, the wife of Prince Louis, and their two sons: Princes Gabriel and Noah. Although Prince Louis and his family are not in the line of succession, they still participate in official events. (source)
Thank you Anne!