During his time as President of the United States, Barack Obama visited the royal family on a number of different occasions, but apparently, during one specific trip to Buckingham Palace, POTUS revealed to one of his staff members that Queen Elizabeth reminded him strongly of his grandmother.
The story is recounted in a new biography of Her Royal Highness by Robert Hardman, titled, Queen Of Our Times: The Life Of Elizabeth II. In his account, Hardman dives into a trip the Obamas made to Buckingham Palace in 2011, where they were hosted by Queen Elizabeth and the late Prince Philip. The story was retold in an article by Newsweek.
As the story goes, the Obamas were at a state banquet when, towards the end of the dinner, a royal household worker kindly asked the attendees to head to their bedrooms because the queen was getting tired. However, Obama wasn't quite ready to hit the hay, so he invited a few of his close staff members into his room for a drink.
According to Obama's speechwriter at the time, Ben Rhodes, this is when the president noted something familiar in the queen. “I really love the Queen,” Obama remarked. “She's just like Toot, my grandmother. Courteous. Straightforward. All about what she thinks. She doesn't suffer fools.”