Despite the fact that Prince William and Kate Middleton are busy parents, they were able to celebrate the most romantic day of the year - Valentine's Day - this year. 

One of the Duke and Duchess of Cambridge's close friends revealed to Us Weekly how the future King of England stunned his wife of 11 years with a surprise. 

"On Valentine's Day, William surprised Kate with a large bouquet of 50 red roses," says the insider. 

Beyond the 50 roses, Prince William and Kate Middleton also shared even more romance with one another. 

"In his card, he wrote the most romantic letter ever, thanking her for being such a wonderful wife and mother," says the insider. 

Their children, Prince George, Princess Charlotte, and Prince Louis, are said to have contributed to the day's success by making homemade Valentine's Day cards at their respective schools. 

After eight years of on-again, off-again dating, Prince William and Kate Middleton tied the knot in April 2011 in London. They first met in 2001 while studying at the University of St. Andrews in Scotland. 

While interviewing for the Duke and Duchess of Cambridge's engagement, the Duke of Cambridge said, "Obviously, we both have a very fun time together, both have a very good sense of humor about things." 

According to the Telegraph, Prince William also said, "We're down to earth, we take the mickey out of each other a lot, and she's got plenty of habits that make me giggle that I tease her about."

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Given the fact that they have been married for more than a decade, they are no longer as interested in expensive Valentine's Day gatherings. 

In addition, the couple is "homebodies," according to the source who spoke to Us Weekly, so it's no surprise that their date evenings are always so laid-back. 

In addition, they stated, "After the children have gone to bed, they'll watch Netflix and documentaries, order takeout, play Scrabble, and enjoy a few glasses of wine." The little things in life are what really matter to them." 

While he couldn't stop raving about his wife and her abilities as a mother, he recently suggested that they might consider adding another child to their family.

"Don't give my wife any more ideas," Prince William quipped to the hospital workers after Kate was pictured cradling a baby during a visit to the facility earlier this month.

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