George Bush Sr has been moved into intensive care after suffering "a series of setbacks that include a persistent fever," according to a family spokesman.
Doctors are "cautiously optimistic" about the 88-year-old former president's health, he added.
Video report by Debi Edward.
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President Obama said he was "mortified" after a man walked up to him at a polling station and warned him not to touch his girlfriend.
Teenagers are being tricked into sending inappropriate photographs through social media, police say.
June and Barry Steenkamp tell Good Morning Britain they accept the judge's decision but still do not believe Pistorius' version of events.