Hyacinthe Gabrielle Roland, a French actress (and possible prostitute) who like "the Polastron," escaped the Revolution. She married Richard Wellesley the first Marquis Wellesley, after they lived together for quite a while and had a few children. One of same, to wit Anne Wellesley, is in Queen Elizabeth's (and therefore Prince Chuck's and Duke William's and Prince George's line, via her mother the Queen Mother's mother's.
Princess Frederica (or Fredericke) is in a private collection.
The Duchesse de Polignac is at the Museum of Versailles and the Trianon
The self-portrait is at the Kimbell Art Museum in Fort Worth, Texas
Hyacinthe Roland, the Queen's ancestor, is the Legion of Honor building of the San Francisco Museum of Fine Arts
Fair winds and following seas :)