"This morning, the vice president accompanied his son Beau Biden to Houston, Texas, where Beau is being evaluated to determine the cause of an episode of disorientation and weakness that he experienced while on vacation with his family last week," the statement from the vice president's office released by the White House said.
A later White House advisory stated the vice president would remain in Houston Tuesday and that he had no public events scheduled.
The younger Biden, 44, suffered what was described as a minor stroke in 2010 that left him hospitalized for a week. Doctors at the time said he was "neurologically normal."
The New York Times reported a Delaware Justice Department spokesman said the attorney general felt weak last Wednesday after driving to Indiana for a family vacation. He first went to Northwestern Memorial Hospital in Chicago and then to to Jefferson University Hospital in Philadelphia to consult with his doctor and spent the weekend at home in Wilmington, Del., before traveling to Houston.