https://rebeccastarrbrown.com/2018/05/01/from-kent-to-bucharest-marie-of-edinburgh-queen-of-romania/

'The Princess’s only respite came from trips abroad when she could visit her mother and Ducky, the latter already trapped in her own unhappy marriage with another first cousin, Duke Ernst of Hesse (eldest son of Queen Victoria’s second daughter, Alice). In May 1896, the two sisters went to Moscow for the coronation of Alix of Hesse and Nicholas II as the Tsar and Tsarina of Russia. Missy later wrote:

Both women had such a good time that they in fact began affairs with two Russian brothers – Grand Dukes Boris and Kyril, the former of which became attached to Missy. Unfortunately for everyone involved, Missy became pregnant in 1897 and it wasn’t clear who the father was. The scandal broke and Bucharest erupted, prompting the Princess to flee for her mother’s house in Coburg.'

and:

'In February 1907 the Romanian Peasants’ Revolt broke out and Missy and her children, alongside a number of noble families, fled Bucharest for the safer distance of Sinaia. There, she took to spending time with her friend, Nadeje Stirbey, and it was via these trips that she struck up a friendship with her husband, Prince Barbo Stirbey. The Revolt ended in April, but her association with the Stirbeys endured. It was under Barbo’s tutelage that Missy began to show a distinct interest in politics and it wasn’t long before the mutual admiration turned into a passionate love affair. '

Not sure about the eccentricities...the previous Queen, Elisabeth, seems to have been the religious nutcase.

Interesting bit of history I knew little about...

and:

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