Background
About 1376, he married Joanna of Durazzo, daughter of Charles, Duke of Durazzo.
About 1376, he married Joanna of Durazzo, daughter of Charles, Duke of Durazzo.
Robert IV inherited the County of Eu on April 6, 1387 along with Saint-Valery and Ault, however, in Naples at the time, he never learned of his father"s death. Robert and Joanna were buried in the church of San Lorenzo Maggiore in Naples. The marriage of Robert and Joanna had remained childless.