Kate Middleton
Kate Middleton, the Duchess of Cambridge, sits next to April, 4, (L), and Sammy, 4, in a pre-school class at the Northside Center for Childhood Development in New York, on Dec. 8, 2014. Reuters/Seth Wenig

Kate Middleton, who recently gave birth to her second child, has called on people to support Children’s Hospice Week, launched by the charity Together for Short Lives. The campaign starts Monday and brings together the U.K.’s 53 hospices and palliative care services aimed at children.

Middleton's request, made in a letter written from Kensington Palace, comes about three weeks after the Duchess of Cambridge gave birth to her second child, Princess Charlotte Elizabeth Diana. Children’s Hospice week is an effort to raise awareness about the nearly 49,000 children in the U.K. with conditions that may not allow them to live a long life.

“For families of children with life-limiting conditions, every moment is precious and every memory needs to be cherished and celebrated,” Middleton wrote in the letter, according to Daily Mail, adding: “Children’s hospices strive to create happy moments in the most difficult times any family could face. I hope you will join me in supporting Children’s Hospice Week and work to make every moment count for all of our families.”

Middleton became a part of East Anglia’s Children’s Hospices (EACH) in January 2012, which is reportedly one of four patronages she became a part of after getting married into the royal family.

“Children’s Hospice Week this year is all about helping children and families make the most of the time they have together. The campaign raises awareness about all the important services supporting these families and how they focus on life - however short it may be,” Barbara Gelb OBE, CEO of Together for Short Lives, said, according to the Mirror, adding: “We hope the public will be inspired to support Children’s Hospice Week this year and help the 49,000 children and their families make the most of their precious time together.”

Middleton and her husband, Prince William, are currently residing in her country home, Anmer Hall, at the Queen’s Sandringham Estate in Norfolk with their 21-month old son George and their newborn daughter.