Prince Harry Wants to Become a Father 'Pretty Soon' After His Royal Wedding With Meghan Markle (Exclusive)

Royal expert Katie Nicholl tells ET that the 33-year-old royal is already looking forward to starting a family with his bride-to-be.

Prince Harry is looking forward to his future with Meghan Markle!

The lovebirds are set to tie the knot at St. George's Chapel on May 19, but according to royal expert Katie Nicholl, author of Harry: Life, Loss, and Love, the 33-year-old royal is already thinking about having kids with his bride-to-be.

"My sources are saying that Prince Harry, particularly, is very keen to start a family, pretty soon after the royal wedding," Nicholl exclusively told ET on Tuesday. "He's made no secret about wanting children."

Harry's brother, Prince William, and his sister-in-law, Kate Middleton, are already parents to two children, Prince George, 4, and Princess Charlotte, 2, with another baby on the way. We had to ask, does this have anything to do with Harry's desire to settle down and start a family of his own?

"I think that moment [for Harry] really kicked in when his brother, Prince William, of course, settled down with Kate Middleton," Nicholl said. "That has definitely gotten Prince Harry pretty broody."

While it's no secret that Harry loves children, we've also gotten a glimpse of Meghan's interactions with kids, through various events she and her fiance have attended in and around London over the past few months as part of their royal duties. Nicholl tells ET that Meghan has already been welcomed with open arms by Prince George and Princess Charlotte.

"Meghan was really keen to obviously meet Prince William and Kate, but she really wanted to meet Princess Charlotte and Prince George," Nicholl explained. "Apparently, it is just a walk across the courtyard from Prince Harry's cottage, which is Nottingham Cottage, to the big house where William and Kate's children live."

"Meghan is very doting with children," Nicholl continued. "She is very maternal and she was thrilled to meet George and Charlotte. I think one of the lovely things, anecdotes that I discovered [while writing] the book was, it was actually a moment involving children, when Meghan really fell for Prince Harry."

And as much as Meghan wanted to meet Charlotte and George on her own, Nicholl says Harry was equally excited to introduce her to them.

"The reason he wanted Meghan to meet Prince George and Princess Charlotte was so she could see that -- this would be hopefully replicated by them, that they would go on to have children," she said. "That you marry into the royal family, but that doesn't mean you can't have a regular family with cute children, and here are George and Charlotte to show that that can happen. That was really important to him."

When Meghan and Harry say "I do" this spring, the toddlers will be by their side. ET previously reported that Prince George and Princess Charlotte will play a special role at the ceremony as page boy and flower girl.

Seeing how they were the center of attention at Aunt Pippa Middleton's wedding last May, we can only imagine all the wonderful pics and videos that will come our way. More on that in the video below!