Hereditary Grand Duke and Duchess are expecting their first child. The announcement was made by the Grand Ducal Palace on Friday. Prince Guillaume and Princess Stephanie will welcome their child next year.

Prince Guillaume, 38, is the eldest son of Grand Duke Henri and Grand Duchess Maria Teresa and is next in line to the title. The royal baby is due in May 2020 and will be succeed Guillaume, whether a girl or a boy. The couple has not revealed the gender of the baby, Luxembourg Times reports.

"Their Royal Highnesses the Grand Duke and Grand Duchess are immensely pleased to announce that the Hereditary Grand Duke and Hereditary Grand Duchess are expecting their first child. The birth is scheduled for May. The Grand Duke, the Grand Duchess and the members of both families are delighted with the news and share their great joy," the statement reads.

De Grand-Duc an d’Grande-Duchesse hunn déi immens grouss Freed matzedeelen, datt den Ierwgroussherzog an d’Ierwgroussherzogin hiert éischt Kand fir de Mee erwaarden. pic.twitter.com/VCn2IoP96L

— Cour Grand-Ducale (@CourGrandDucale) December 6, 2019

The palace released a series of photographs of the couple to announce the news. In two pictures the royal couple are smiling at the camera as they pose outside. Guillaume is dapper in a navy blazer paired with white open-collar shirt and camel-coloured trousers his wife Stephanie wears jeans and a blue top.

Leurs Altesses Royales le Grand-Duc et la Grande-Duchesse ont l’immense joie d’annoncer que le Grand-Duc héritier et la Grande-Duchesse héritière attendent Leur premier enfant pour le mois de mai. pic.twitter.com/hQFZKLdkB7

— Cour Grand-Ducale (@CourGrandDucale) December 6, 2019

In another set of photos, the parents-to-be looked are dressed formally. The prince wears black suit and trousers with white shirt and tie, while the princess glows in a purple blazer and jeans.

"I don't have any plans to become a mother. For the moment, I'm enjoying spending time with my husband," said Stephanie speaking to French magazine Point de Vue in 2016, when there were rumours about her pregnancy.

kate middleton
Britain's Catherine, Duchess of Cambridge, (L) arrives with Belgian Countess and wife of Hereditary Grand-Duke of Luxembourg Stephanie de Lannoy during the Celebration of the 150th anniversary of the 1867 Treaty of London in Luxembourg, on May 11, 2017 JOHN THYS/AFP/Getty Images

Guillaume and Stephanie married in 2012 at the Notre Dame Cathedral in Luxembourg City. The princess belongs to the de Lannoy family in Belgium. Guillaume is the heir apparent of Luxembourg and is the eldest child of Grand Duke Henri Luxembourg and his wife Grand Duchess Maria Teresa. He has four younger siblings, Prince Félix, Prince Louis, Princess Alexandra and Prince Sébastien.