After feeling weak and disoriented during a drive to Indiana last week, Beau Biden is in Houston for medical tests to determine what's causing those symptoms.

UPDATE: Biden tweeted out a thank you message for all the well wishes he's been receiving since it was announced that he traveled to Houston for tests, "Touched by all your well wishes--thank you. Nice evening in Houston w/ Hallie; will share update when we have it. -bb"  Biden also posted a picture of himself smiling with his wife.

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ORIGINAL STORY:

The 44-year-old son of Vice President Joe Biden is undergoing tests in Texas Tuesday. He first felt weak and disoriented after a long drive to Indiana for a family vacation last Wednesday. He was admitted to Northwestern University Hospital that night. The next day he traveled back home to meet with his doctor at Jefferson University Hospital in Philadelphia to consult about his earlier symptoms. 

Biden spent the weekend at his home in Wilmington, then traveled to Texas for more tests.

In May 2010, Biden had a big medical scare when he suffered a mild stroke. He took about a month off to recuperate from that incident. It's not clear whether his latest health problems are in any way related to his previous stroke.

Biden's staff said he spoke by phone with Chief Deputy Attorney General Ian McConnel over the weekend and was in touch with the office last night.