 The Coburgs , as they came to be called , spent the Christmas holidays at the Brighton Pavilion with various other royals . On 7 January , the Prince Regent gave a huge ball there to celebrate Charlotte 's 21st birthday , but the Coburgs did not attend , having returned to Claremont and preferring to remain there quietly . At the end of April 1817 , Leopold informed the Prince Regent that Charlotte was again pregnant , and that there was every prospect of the Princess carrying the baby to term . 
