her third pregnancy her third pregnancy is due with the couple's third child royal baby is due in April early is due with the couple's third child is due in April of 2018 third child arrives in April expected to arrive Will and Kate's third child is due Duke and Duchess of Cambridge's third child is born. which is due in April of 2018 her third pregnancy her third pregnancy is due with her third child in April her third pregnancy her third pregnancy early which is due in April of 2018 earlier than a royal usually would which is due in April of 2018