Dorothea von Ertmann
... that Beethoven improvised for an hour on piano to comfort Dorothea von Ertmann, his student and possible Immortal Beloved, over the death of her son?
... that <a class="mw-redirect" href="./Beethoven" id="mwDHk" rel="mw:WikiLink" title="Beethoven">Beethoven</a> improvised for an hour on piano to comfort <b id="mwDHo"><a href="./Dorothea_von_Ertmann" id="mwDHs" rel="mw:WikiLink" title="Dorothea von Ertmann">Dorothea von Ertmann</a></b>, his student and possible <a href="./Immortal_Beloved" id="mwDHw" rel="mw:WikiLink" title="Immortal Beloved">Immortal Beloved</a>, over the death of her son?