In 1867, Konstantin's eldest daughter, Olga, married King George I of Greece.
She was only sixteen, and Konstantin was initially reluctant to let her marry so young.
In July 1868 Olga's first child was born and was named Konstantin after his grandfather.
The start of his daughter's family coincided with the breaking up of Konstantin's marriage.

Although he was only forty, Konstantin's struggles and travails of the previous decade—naval and judiciary reforms, the freeing of the serfs—had prematurely aged him.
As Alexander II turned away from the reforms that had marked his first decade on the throne, Konstantin's influence began to wane and he began to focus more in his personal life.
After twenty years of marriage he had drifted away from his wife, their divergent political views and interests slowly tearing away the foundations of their marriage.
Alexandra Iosifovna was as conservative as her husband was liberal, self-absorbed with her own beauty and her mysticism.
Soon, Konstantin turned elsewhere for comfort.

At the end of the 1860s, Konstantin embarked on an affair, having an illegitimate daughter, Marie Condousso.
In the 1880s, Marie was sent to Greece, later serving as lady in waiting to her half sister, Queen Olga.
Marie eventually married a Greek banker.
Soon after the birth of Marie, Konstantin began a new liaison.
Around 1868, Konstantin began to pursue a young dancer from the St. Petersburg Conservatoire.
Anna Vasilyevna Kuznetsova was a talented ballerina and a mime.
She was the illegitimate daughter of ballerina Tatyana Markyanovna Kuznetsova and actor Vasily Andreyevich Karatygin.
Anna was twenty years younger than Konstantin and initially she resisted his advances, but in 1873 she gave birth to their first child.
Four more would follow.

Konstantin bought his second family a large, comfortable dacha on his estate at Pavlovsk, in fact lodging his mistress and their illegitimate children in close proximity to his estranged wife who he now referred to as his "government–issue wife".
Once more Konstantin gave ammunition to his enemies and society sided in the scandal with his suffering wife, who tried to bear his infidelity with dignity.

In 1874, scandal erupted when it was discovered that Konstantin's eldest son, Grand Duke Nikolay Konstantinovich, who had lived a dissipated life and had revolutionary ideas, had stolen three valuable diamonds from an icon in the bedroom of Alexandra Iosifovna in complicity with his mistress, an American courtesan.
His twenty-four-year-old son was found guilty, declared insane, and banished for life to Central Asia.
Konstantin suffered another bitter blow when in 1879, his youngest legitimate son, Vyacheslav, died unexpectedly from a brain hemorrhage.
In 1867, Konstantin's eldest daughter, Olga, married King George I of Greece. She was only sixteen, and Konstantin was initially reluctant to let her marry so young. In July 1868 Olga's first child was born and was named Konstantin after his grandfather. The start of his daughter's family coincided with the breaking up of Konstantin's marriage.
Although he was only forty, Konstantin's struggles and travails of the previous decade—naval and judiciary reforms, the freeing of the serfs—had prematurely aged him. As Alexander II turned away from the reforms that had marked his first decade on the throne, Konstantin's influence began to wane and he began to focus more in his personal life. After twenty years of marriage he had drifted away from his wife, their divergent political views and interests slowly tearing away the foundations of their marriage. Alexandra Iosifovna was as conservative as her husband was liberal, self-absorbed with her own beauty and her mysticism. Soon, Konstantin turned elsewhere for comfort.
At the end of the 1860s, Konstantin embarked on an affair, having an illegitimate daughter, Marie Condousso. In the 1880s, Marie was sent to Greece, later serving as lady in waiting to her half sister, Queen Olga. Marie eventually married a Greek banker. Soon after the birth of Marie, Konstantin began a new liaison. Around 1868, Konstantin began to pursue a young dancer from the St. Petersburg Conservatoire. Anna Vasilyevna Kuznetsova was a talented ballerina and a mime. She was the illegitimate daughter of ballerina Tatyana Markyanovna Kuznetsova and actor Vasily Andreyevich Karatygin. Anna was twenty years younger than Konstantin and initially she resisted his advances, but in 1873 she gave birth to their first child. Four more would follow.
Konstantin bought his second family a large, comfortable dacha on his estate at Pavlovsk, in fact lodging his mistress and their illegitimate children in close proximity to his estranged wife who he now referred to as his "government–issue wife". Once more Konstantin gave ammunition to his enemies and society sided in the scandal with his suffering wife, who tried to bear his infidelity with dignity.
In 1874, scandal erupted when it was discovered that Konstantin's eldest son, Grand Duke Nikolay Konstantinovich, who had lived a dissipated life and had revolutionary ideas, had stolen three valuable diamonds from an icon in the bedroom of Alexandra Iosifovna in complicity with his mistress, an American courtesan. His twenty-four-year-old son was found guilty, declared insane, and banished for life to Central Asia. Konstantin suffered another bitter blow when in 1879, his youngest legitimate son, Vyacheslav, died unexpectedly from a brain hemorrhage.
Grand Duke Konstantin Nikolayevich of Russia