In 1805, John Anton Vidic, a widowed 63-year-old toller in Kostanjevica na Krki, gave birth to an illegiti mate daughter from his relationship with his 28-year-old niece Jožefa, the daughter of his deceased brother. The child was baptised in the neighbouring parish of Raka, and Vidic asked the Ljubljana Archdiocesan Ordinariate for permission to marry, but because of the complicated and expensive procedure - the decision would have to have been made in Vienna and Rome - was denied it. T he second part of the paper deals with the social and genetic background of unmarried spouses - uncle and niece. It was a family of tollers and merchants, whose roots went back to the towns of Kamnik, Ljubljana and Radovljica, whose ancestors included town magistrates and councillors, and whose close family included five priests in three generations from the end of the 17th century onwards. Like Janez Anton Vidic, many of his relatives attended the Jesuit Gymnasium in Ljubljana.