LONDON (AP) — The Duke and Duchess of Cambridge have confirmed that their second baby is due in April — the first time they have offered a month for the royal birth.

Kensington Palace also said in a statement Monday that the duchess, who has been sidelined by prolonged morning sickness, continues to improve. There was no word on the baby’s gender.

The former Kate Middleton and Prince William are scheduled to welcome Singapore President Tony Tan when he arrives on a four-day state visit this week. She is also expected to attend the Wildlife Photographer of the Year 2014 award ceremony.

The duchess canceled several engagements after her second pregnancy was announced in September. She also had acute morning sickness during her pregnancy with Prince George, who was born in July 2013.

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