Prince William and Kate Middleton
Kate Middleton and Prince William are unlikely to bring their newborn to Prince Harry and Meghan Markle's royal wedding. Pictured: Prince William and Middleton pose for photographers with their newborn baby boy outside the Lindo Wing of St Mary's Hospital on April 23, 2018 in London. Getty Images/Jack Taylor

Kate Middleton and Prince William are likely to attend Prince Harry and Meghan Markle's royal wedding without their newborn.

The Duke and Duchess of Cambridge just welcomed their third baby on Monday. The now parents of three are expected to attend Prince Harry and Markle's nuptials, but they will likely leave Prince George and Princess Charlotte's sibling at home during that event for a reason, according to a royal expert.

"They certainly won't bring the baby to the wedding, this will ensure that the focus is on Harry and Meghan as of course it should be," Richard Fitzwilliams said.

Meanwhile, Prince George and Princess Charlotte are expected to be present for their Uncle Harry's wedding. In fact, the two are predicted to be part of the royal wedding entourage as the page boy and flower girl or bridesmaid, respectively.

"It is certainly expected that Prince George and Princess Charlotte are page boy and flower girl or bridesmaid," Fitzwilliams said. "There is long royal tradition where royal children play key roles at weddings which is charming."

Aside from Prince George and Princess Charlotte's charm, another expert believes that their close relationship with the groom-to-be is enough reason to include them in the royal wedding. In fact, according to Marlene Koenig, she would be "shocked" not to see the young royals with significant roles in Prince Harry and Markle's nuptials.

"George and Charlotte are Harry's only niece and nephew, so it would be a real shocker if they were not included," Koenig explained. "In Britain, the bride goes down the aisle first, followed by attendants or bridesmaids and page boys holding the train."

Meanwhile, Prince Harry and Markle decided not to give Middleton any role on their wedding. The couple knew that the Duchess would be busy with her newborn at that time and only wanted her to enjoy the event.

"Frankly, Harry and Meghan are just happy that Kate will be there given she will only just have given birth," a source told Vanity Fair. "They have told her there is no pressure on her to do anything, they just want her to enjoy the day."

Prince Harry and Markle are tying the knot on May 19 at St. George's Chapel at Windsor Castle.