Kate Middleton visited the Northside Center for Child Development in Harlem, New York, on Monday, Dec. 8, followed by an intimate luncheon with successful Brits in NYC at the Consul General's private home. Credit: Mark Stewart - Pool/Getty Images

Who wants to build a snowman with Kate? Duchess of Cambridge Kate Middleton visited the Northside Center for Child Development in Harlem, New York, on Monday, Dec. 8, where she was mistaken for a famous film princess by the kids.

For her first engagement in the Big Apple, Prince William's wife toured the facility with Chirlane McCray, wife of the city's mayor Bill de Blasio. Inside the Child Development Center, the two met privately in the library with families, and children ages 2 to 18 experiencing developmental delays, in addition to young victims of abuse.

The Duchess and NYC's First Lady (in a Nanette Lepore Skyscape Coat) then walked to the gift-wrapping station, where items including Frozen paraphernalia, Dr. Seuss books, and a singing butterfly waited to be wrapped. Middleton proved proficient in the art of gift wrap as she deftly placed tape on her thumb, used scissors to cut the paper, and even scrawled a message atop the wrapping paper for a child "3-24 months."

Prince George's mom joked that she had hoped they would have given her a "square" gift to wrap, but she packaged the singing winged butterfly beautifully. After she finished wrapping the item, the Duchess clutched it with both hands and held it up as if she was announcing it as a feat. McCray, meanwhile, handed her a red bow to add a festive touch.

Later, the Duchess, 32, was led into a classroom filled with 3- and 4-year-old kids with special needs. "Do you know who's coming to visit today?" an administrator asked as Middleton made her entrance.

"Princess!" a little girl named April shouted.

The Duchess was told in advance that the children liked Disney's smash animated flick Frozen, which she used as an opening line for conversation.

"Do you really like Frozen?" she asked several kids.

The pregnant royal then turned to a boy named Sammy, whom she tasked with putting stickers on his friends.

It turned out that the children thought the Duchess was actually a real-life incarnation of Elsa from the movie. "They thought she was the princess from Frozen," administrator Rose Ann Harris told Us Weekly of the center's students.

Assistant director of finance Sharon Fraser watched the Duchess greet fans outside East 110th Street and remarked: "She's so adorable. She's loving it. She's enjoying it."

Middleton's engagements continued Monday afternoon with a luncheon at the British Consul General's private residence. The gorgeous penthouse included sweeping views of the city, as well as a Christmas tree, and poinsettias scattered on the floor throughout the entire home. The menu was comprised of pressed vegetable terrine infused with herbs, poached salmon with dill hollandaise sauce, and apple and rhubarb crumble with ice cream.

Nine successful Brits living in NYC were asked to attend the luncheon, including Mashable founder Pete Cashmore, Saks president Marigay McKee, NBC News president Deborah Turness, as well as Danny and Susan Lopez. All are strong supporters of the Consulate on a regular basis.

"She's very nice, very sweet, very interested in the industries we are in and what British entrepreneurs are doing in the U.S.," Cashmore told Us. "We talked about how media is a very exciting place to be right now, there's a lot of change… She is very excited about the Internet industry, you know, understands it is a fast-paced business to be in."

Famed producer Colin Callender of Playground Entertainment praised Middleton as "an icon." He joked: "My daughters [ages 11 and 13] are over the moon. They wanted to come. They said, 'Daddy, we’ll hide behind your suit jacket.'"