Another concertgoer also caught the "Blank Space" singer dancing with pop trio Haim during JT's show. The sisters and Swift were celebrating Alana Haim's 23rd birthday. "Happy birthday @babyhaim!" Swift tweeted. "So happy I got to watch you blow out your candles while you were singing a scandalous/perfect rap song. As you do."
Timberlake tweeted after performing in front of his star-studded audience, writing: "Nothing like being at sold-out Barclays with the King of Brookyln... #JT2020Tour."
This past October, Swift chatted with ET about her famous friends, disclosing what quality she finds most important in a gal pal. "A good girlfriend for me is someone who is an individual and has something that they are deeply passionate about," she said.
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