Michelle Obama took her girls to visit the set of the film Harry Potter and meet the cast.
The first family visiting the set where "Harry Potter and the Deathly Hallows" is being filmed and celebrated Sasha's eighth birthday with the cast and crew on the film with a party in the Great Hall, the Daily Telegraph reported.
Sasha and Malia, 10, both big Harry Potter fans, toured North London's Pinewood Studios with their mother and reportedly met stars Daniel Radcliffe, Emma Watson and others from the boy-wizard series, the Times (U.K) reported.
"They girls like Harry Potter," a spokeswoman for the first lady told Politics Daily.
Michelle, her mother, Marian Robinson, and the two girls flew to Paris last Friday to meet up with President Obama ahead of events marking the 65th anniversary of D-Day over the weekend.
The Obamas made a surprise stop-over in London on Monday and have gone sightseeing in the city -- taking in Big Ben, Westminster Abbey, the Tower of London, according to ABCNews.com.
The first lady took her daughters to see the musical The Lion King in London's West End on the eve of Sasha's birthday.
"The children were clearly having a good time," an audience member told People magazine. "There was quite a buzz in the theater once people spotted them during the first part."
"I saw the girls skipping back into their box from their private room," the person said.
On Monday, they visited Downing Street and the Houses of Parliament before they hunkered down for traditional English fare at The Audley pub for dinner. The girls ate fish and chips and Michelle opted for a juicy sirloin.