The British royal, 36, and her husband, Edoardo Mapelli Mozzi, welcomed the newest addition to their family in January, when baby Athena Elizabeth Rose was born several weeks premature.
Dara Huang, an American architect and designer, shares her son Christopher Woolf - known affectionately as 'Wolfie' - with her former fiancée Edoardo Mapelli Mozzi.
On Wednesday, 28 January, Buckingham Palace confirmed King Charles' niece, 36, and her husband Edoardo Mapelli Mozzi had welcomed their second child together last week.