The accession to power in Pyongyang of Kim Jong Un, son of Kim Jong Il and grandson of Kim Il Sung, is a unique achievement in world politics. How many other non-monarchical regimes have managed to retain power through immediate succession for three generations?
There are examples of fraternal dictatorships, or one anyway: the passing of power from Fidel to Raul Castro. There are several husband and wife teams, and this appears to be an Argentine specialty. After Juan Peron died his wife Isabel took the presidency, from which she was evicted by a military coup two years later. (Evita predeceased Peron and had never been a public official.) More recently, Nestor Kirchner was followed by his wife Cristina, who was reelected this year for another term. Lest Americans become overly snooty about such practices, remember that Lurleen Wallace followed George as governor of Alabama. Nor is this unique: Gov. James Ferguson of Texas got his wife Miriam, better known as Ma Ferguson, elected governor twice in the 1920 and 1930s. (Nellie Tayloe Ross was elected governor of Wyoming in 1924 after the death of her husband, William, but that doesn't count. She got elected fair and square.)