Prince William and Kate Middleton look undeniably good together. But more than the prestige of being the ideal royal couple, how do these two manage to work their differences?

William may be next in line to be king after Prince Charles takes over the throne, but his real partnership with Kate is what will truly prepare him for the throne. The Duke of Cambridge has his intense side and Kate balances it with poise and calmness, making them strong partners for each other. 

A close friend told PEOPLE that Kate and William look after each other but in different ways. Some say that theirs is an "old-fashioned" marriage because they look out for each other -- something that works for them. 

His and Her Role

Prince William has his own role and Kate has her own, but together, the two of them come as a team. The Duke and Duchess of Cambridge, both 37, were seen with great teamwork during their tour in Pakistan in October.

According to a senior royal source, people always admire William for the speeches he makes, but the presence of Kate brings something to the table, too. When she spends time talking to Presidents and their wives, she is able to add to the comfort. "They are a great double act," the source said.

All these are beneficial to the monarchy when they do it side by side. 

All the royal travels to represent the U.K. are decided upon by the Foreign Office. They see the royal couple as a massive asset to the country because the perception of them as a couple is positive and very strong. An insider told PEOPLE that there are already two major tours overseas lined up for the duo. 

The roles that they play in their marriage greatly impact their roles as members of the royal family. How they provide support to each other also says a lot about how the public sees them. At the moment, the Prince William and Kate seem like the royal couple to beat.

Indeed, they have raised the bar as to how royal marriages should be. 

A Strong Foundation

In truth, Prince William was given a strong foundation to build himself compared to his father. Prince Charles grew up with a distant relationship from his mother that by the time he was William's age, he already found himself in an unhappy marriage with the late Princess Diana.

In contrast to the ugly split of his parents, Prince William was given a nurturing childhood. Later on, he received the same support from the parents of Kate -- Carole and Michael Middleton. 

Kate, on the other hand, may come from a simple family, but she grew up with all the love and support she could need. The confidence that she exudes now as the Duchess of Cambridge is a product of the happy childhood she had.

In fact, the couple is raising their three kids as normal as possible despite their royal stature. In one of her recent interviews, Kate emphasized how she and William want their kids to experience a normal childhood. 

How does this royal marriage work? According to the historian Robert Lacery, the Duke of Cambridge is better grounded than any of his predecessors. This is the secret to his successful marriage with Kate. He knows what he wants and works hard to keep it. 

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