New parents PRINCE WILLIAM and CATHERINE, DUCHESS OF CAMBRIDGE left hospital with their new bundle of joy on Tuesday evening (23Jul13), a day after the royal baby arrived at London's St. Mary's Hospital. The royal couple greeted fans and the media on the steps of the Paddington hospital. William smiled and waved as his beaming wife cradled their child in her arms. She then handed the baby boy to her husband and the pair stepped out into the street to speak to reporters. Prince William said, "He's got a good pair of lungs on him, that's for sure.