People reported Wednesday that onlookers saw the couple at Teddy's nightclub at the Roosevelt later that night, where Simpson "showed off some sexy moves" to Whitney Houston's "I Wanna Dance With Somebody."
But a source tells US Weekly that Simpson and Ross are just friends:
"Evan and Ashlee have been friends for a really long time, probably ten years. They know each other from the club scene and have tons of mutual friends."
Simpson has a son, four-year-old Bronx Mowgli, with ex-husband Pete Wentz.