|Constantine of Russia|
Anna returned to Coburg in 1801. In 1808 she gave birth to an illegitimate son, named Eduard Edgar Schmidt-Löwe. The father of this child may have been Jules Gabriel Émile de Seigneux, a minor French nobleman and officer in the Prussian army. In 1835 Eduard married his cousin Bertha von Schauenstein, an illegitimate daughter of Juliane's brother Ernest.
After 19 years of separation, the marriage of Constantine and Juliane was formally annulled on 20 March 1820. Two months later, on 27 May, Konstantin married the Polish Countess Joanna Grudzińska (1791-1831), his mistress since 1815. She was given the title of "Her Serenity" Princess of Lowicz. The new Princess's health was poor; she had migraines, fevers and rheumatism, and led a quiet life.
Grand Duke Constantine died of cholera in Vitebsk (now Belarus) on 27 June 1831. Joanna accompanied his body to Saint Petersburg, dying the same year.