Born on 11 November 1981, Guillaume Jean Joseph Marie, Hereditary Grand Duke of Luxembourg, Prince of Nassau and Bourbon-Parma, celebrates his 39th birthday today.

The eldest son of Grand Duke Henri and Grand Duchess Maria Teresa was officially appointed Hereditary Grand Duke on 18 December 2000. He married Countess Stéphanie de Lannoy on 19 October 2012.

From 2018 to 2019, the Hereditary Grand Duke and his wife lived in London, where Prince Guillaume followed a postgraduate course at the Royal College of Defense Studies, in order to acquire additional expertise to assume his future responsibilities as Head of State in the best possible conditions. This course of study was in line with the training followed by the Hereditary Grand Duke at the Sandhurst Military Academy in 2001.

On 10 May 2020, Hereditary Grand Duke Guillaume became a father for the first time: Crown Prince Charles Jean Philippe Joseph Marie Guillaume was born in the Grand Duchess Charlotte Maternity Hospital in Luxembourg City at 5.13 am.