Prince William and Kate's baby due in April

Kate Middleton is still suffering from Hyperemesis Gravidarum, which is acute morning sickness.

Britain's Duke and Duchess of Cambridge, Prince William and Kate, in Sydney in April 2014. Picture: EPA.

LONDON - The second child of Britain's Prince William and his wife Kate is due to be born in April, his office announced on Monday.

William, grandson of Queen Elizabeth and second-in-line to the throne, announced last month that Kate was expecting a second baby to join Prince George who was born in July last year, but no date for the birth was disclosed at the time.

The statement from William's office also confirmed that Kate is still suffering from Hyperemesis Gravidarum, acute morning sickness which causes severe nausea and vomiting and requires supplementary hydration and nutrients.

The condition has caused her to cancel a number of official engagements.