"The three of them have built up a relationship with the President and First Lady over the years," a palace source tells PEOPLE
Prince George made a surprise appearance at Kensington Palace on Friday – in his pajamas!
The little royal, who stole the spotlight earlier in the week in his cutest royal portrait yet, appeared in a hallway wearing a plush robe (embroidered with his name!), matching gingham blue pajamas and slippers just before the start of his parents’ dinner with President Barack Obama and First Lady Michelle Obama.
In a photo shared on Kensington Palace’s Twitter, George can be seen sharing a handshake with the President. Other pictures show him riding a rocking horse – a gift from the Obamas when he was born.
Although George, who turns 3 in July, was permitted to stay up late for the special occasion, his nearly 1-year-old sister Princess Charlotte was fast asleep, says a palace source: “George stayed up for a few minutes when the President and the First Lady arrived, but Charlotte was in bed.” (George had previously been playing with a plush version of First Dog Bo, a past gift from the Obamas.)
The special evening – which followed lunch Buckingham Palace with the Queen – was arranged by William on behalf of all three royals, and “they were delighted that [the First Couple] were able to accept,” a palace source tells PEOPLE.
“The three of them have built up a relationship with the President and First Lady over the years,” adds the source.
Of course, Prince Harry has his own special relationship with the White House – and in particular with Mrs. Obama.
Last June, he hosted the First Lady and First Daughters Malia and Sasha – along with grandma Marian Robinson – for tea at Kensington Palace.
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Then in October, it was the First Couple’s turn to play host to a visiting Prince Harry – where the chemistry between Mrs. Obama and the royal was on adorable display.