Pippa Middleton at US Open
Pippa Middleton, the sister of Catherine, Duchess of Cambridge, arrives at the gallery at the U.S. Open tennis tournament in New York, 4 September, 2012. REUTERS/Eduardo Munoz

Pippa Middleton, younger sister to the Duchess of Cambridge, made a splash last weekend when she jumped the pond to New York. Besides taking in the sights, the 28-year-old British socialite was also linked to a number of eligible bachelors, including hotelier Andre Balazs, who reportedly hosted her during the trip.

Middleton was flown out on Sunday to posh Shelter Island, at the east end of Long Island, in a seaplane owned by Balazs to the 55-year-old mogul's Sunset Beach hotel. According to a source for the New York Post, Middleton was spotted playing pingpong with the businessman, who is reportedly worth more than $450 million, and there was "definite chemistry between the pair." They also drove around town together in Balazs's VW van, and dined together on Sunday night.

"They were taking pictures and popping their heads out of the van, smiling and laughing the whole time," added the source. "Andre was being very charming."

For her part, Middleton seemed right at home in the States. According to Perez Hilton, the party planner, who is in town for a meeting with publishers about her coming book, "Celebrate: A Year of Festivities for Families and Friends," was spotted "walking around with bare feet, holding her wedges in her hand."

Before to her Hamptons sojourn, Pippa kicked off her New York visit Saturday night in style at the Carlyle Hotel on the Upper East Side of Manhattan, where she stayed with two girlfriends, reported the Daily Mail. Soon after checking in, she dashed downtown to the Meatpacking District, where she caught dinner with friends at the Asian fusion restaurant Catch and stayed for "just over an hour," according to the Post's Page Six.

Apparently a fan of the bustling neighborhood, Pippa also visited the Electric Room at the Dream Downtown hotel, and was seen talking to Sean Avery, the 32-year-old former New York Ranger. But unlike her sister's brother-in-law, Prince Harry, Middleton apparently knew when it was appropriate to duck out. According to a source for the New York Daily News, "she was only there for a short time."

For her last event of the long weekend, Middleton journeyed out to Flushing Meadows on Monday, at the behest of Roger Federer, where she enjoyed a guest pass at the U.S. Open and wowed onlookers in a snug color-blocked frock.

Middleton, who turns 29 on Thursday, has also been widely speculated to join the tents for New York Fashion Week, but there has been no sign of Alex Loudon, her on-again-off-again boyfriend, in New York.