Joseph Stalin had one daughter, Svetlana Alliluyeva who died in Wisconsin on November 22, 2011, at the age of 85. However, the Soviet leader had two sons from his two wives. Stalin’s first wife was Ekaterina Svanidze who gave birth to Joseph’s first son who was born in 1907 and who died in a German concentration camp in 1943. Ekaterina was Stalin’s great love, and they married in 1906. Unfortunately, she passed away from typhus when she was only 22 and when her son was barely nine months old. This affected Stalin greatly, and if Ekaterina had lived, Stalin the dictator wouldn’t have been born. At her funeral, he told one of his friends: ‘This creature softened my heart of stone. She died and with her died my last warm feelings for humanity.’
Yakov Dzhugashvili Stalin

Although he loved his wife greatly, he wasn’t nourishing the same feelings for his son Yakov. Yakov or Yasha as his father called him had a difficult life, and at one point he tried to shoot himself, but he missed. As he was bleeding Stalin just said: ‘He can’t even shoot straight.’
Yakov Dzhugashvili was a lieutenant in the artillery in the Red Army as the country was preparing for the World War II. When he was about to go to war, his father told him ‘Go and fight,’ but he was captured by the Nazis and taken prisoner. Speaking of prisoners, Stalin said: ‘There are no prisoners of war only traitors to their homeland.’ He failed his father, and he admitted that he tried to shoot himself during the interrogation. His father would have probably respected him more if he managed to take his life away.
Yakov was married to a Jewish girl Julia, and Joseph became quite fond of her. However, when Yakov was captured, Julia was arrested too, and she was sent to the gulag, a labor camp created by Lenin which reached its peak during Stalin’s rule. Since Joseph considered the prisoners to be the traitors, Julia had to be imprisoned despite the fact that she was family. Joseph brokered her release, but she was forever traumatized by the experience at the camp.
The Germans advised Russian to give up from fighting, and they used Yakov as an example. They said that he was alive and well and that the others should follow Stalin’s son. At one point, Russians captured German Field Marshal Friedrich Paulus and the Nazis offered an exchange of prisoners – Yakov for Freidrich – to which Joseph said: ‘I will not trade a Marshal for a Lieutenant.’
Yakov Dzhugashvili died shortly after he heard of the Katyn massacre. Stalin ordered the murder of 15,000 Polish officers and some of them were Yakov’s friends. This was too much for him to bare, and a 36-year-old Stalin’s son threw himself onto an electric fence.
Vasily Dzhugashvili Stalin

Stalin’s second wife was Nadezhda Alliluyeva who gave birth to Stalin’s second son Vasily Stalin and his daughter Svetlana, five years later. Vasily was born in 1921, but when he was 11 years old, his mother Nadezhda shot herself because she was suffering from depression. This was too much for the young Vasily, who joined the aviation school at the age of 17 although he didn’t have the grades for it. According to Joseph, Vasily was a ‘spoilt boy of average abilities.’ However, Vasily was no fool, and he used his father’s name to get special treatment, but when the news reached his father, he ordered an immediate end to such a folly.
Vasily Stalin kept using his name to get the perks of life. He managed to become a pilot despite his excessive drinking, and he was a womanizer. He would fly planes while intoxicated and even though he was married twice, he always had mistresses. At the beginning of the war he became a colonel, and in 1946 he was a Major-General, which was far above his abilities.
Vasily was not popular because of his drinking problems, but he was afraid of no-one mostly because of his father’s reputation. However, he was scared of his father, and he lived in constant fear of what would happen to him after Joseph dies. And he was right to be afraid. After Stalin’s death, Vasily was dismissed from the air force and arrested for ‘misappropriation of state property.’ In other words, he used the funds from the air force in private purpose. Nikita Khrushchev succeeded Stalin, and this was the time when Vasily Stalin was released, but he ended back behind bars in less than a year for a traffic accident. He was exiled to Kazan after he was released due to ill health, but he died on 19 March 1962, just two days before his 41st birthday.
Source: historyinanhour.com