"There is a deep rift within the band," the group's representative Jesse Derris told People.com. "There was a big a disagreement over their music direction."
Their 19-date tour was to kick off Friday, but was scrapped after the siblings -- Nick, 21, Joe, 24, and Kevin, 25 -- had a huge argument.
Asked what the future holds for the brothers, Derris told People.com, "It remains to be seen."
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