Pàmela Labunska (1837-1901), wife of Otto, Prince of Schönburg-Waldenburg (himself son of Fürst Otto Victor and Thekla of Schwarzburg-Rudolstadt), daughter of Apollinaris Labunski and Iuliana Popow.
I was wondering who she was, her origins are obscure. Did she had a title, or maybe was she an heiress? Anyway, it doesn't this marriage was considered morganatic as her children were all prince/princess of Schönburg-Waldenburg with the style of Serene Highness.
Otherwise, she was the grandmother of Sophie of Schönburg-Waldenburg, Pss zu Wied, Pss of Albania, through her son Erbprinz Victor and his wife Lucia of Sayn-Wittgenstein-Berleburg.
So if anyone has additional information, feel free to post!