A large part of Princess Kate's work as royalty revolves around early childhood development.

As a parent and campaigner, Princess Kate has developed many effective tricks to keep her children from moving around during solemn official events.

Body language expert Judy James told the Express that Kate "tends to keep her cool even at the most tense royal events."

Commenting on the latest appearance of Prince Louis on the Buckingham Palace balcony at the coronation, James said, "Kate seems adept at using calming touch rituals to induce Louis to play less when necessary, but does not appear to admonish him."

While this may be effective in some ways, James warns that it "could escalate to tears and tantrums."

Instead, Kate connected with her youngest with "small, regular tie signs that touch the back (reminding Prince Louis to remain calm while allowing him to feel quite free."

According to experts, the Welsh couple's brief display of affection, "sometimes a pat or pat on the head as a reward when the children are particularly well-behaved."

The couple's "affection for the children is also expressed in the way they are treated by the parents.

James believes this is a positive strategy: "Encouraging good behavior is often a more effective motivator than scolding mischief," she says.

Besides, Louis' sister, Princess Charlotte, is usually around to make sure he follows royal protocol. These kids are too cute.