Royal Family
Prince George and Princess Charlotte have to share their newest gift to their upcoming sibling. Pictured: Kate Middleton, Princess Charlotte, Prince Willilam and Prince George at a children's party for Military families during the Royal Tour of Canada on Sept. 29, 2016 in Victoria, Canada. Getty Images/Chris Jackson

Kate Middleton received a present for her kids in one of her royal engagements this week.

On Tuesday, Middleton stepped out on her own to visit Pegasus Primary School. During the said visit, one of the children presented the Duchess of Cambridge with a lullaby book. The gift was addressed to Prince William and Middleton's children 4-year-old Prince George, 2-year-old Princess Charlotte and the upcoming third royal baby.

"You've had the practice of singing to your kids," said 8-year-old Joyce Mobeka when she handed the gift to Middleton.

On the first page of the book, there's a note that read: "A collection of stories, poems and lullabies written by the children of Pegasus School." It was dated March 6, 2018.

The present was meant to be shared by the Duke and Duchess of Cambridge's three children. This is not the first gift that Prince George and Princess Charlotte's upcoming sibling has received.

In February, when Middleton and Prince William visited King Harald and Queen Sonja, the royals from Norway gave the Duke and Duchess of Cambridge presents. There were also gifts for Prince George, Princess Charlotte and the third royal baby. One note in the gift reads: "For the Prince or Princess to come!"

Middleton's visit to the school was to learn more about the charity Family Links that empower children, parents, families, schools and workplaces for positive emotional health. A group of children ages 6 years old and above met with the Duchess and shared their experience with the charity.

"'It helps us get all our emotions out so we don't feel all bottled up. You don't think about it so much. You tell someone, and when you've told someone it makes you feel a lot better," Jodie Brackett, 11, said during the discussion.

Middleton is already a few weeks away from her due date, but the Duchess is not slowing down with work. On Monday, she is set to join Queen Elizabeth II, Prince Charles, Prince William, Prince Harry and Meghan Markle for the Commonwealth Day celebration at Westminster Abbey.

Some royal fans are betting that Prince William and Middleton's third royal baby is due on St. George's Day. Meanwhile, if it arrives on a later date it might coincide with the Duke and Duchess' seventh wedding anniversary on April 29 or Princess Charlotte's third birthday on May 2.