From CBS News' Steve Chaggaris and Maria Gavrilovic:
Barack Obama's grandmother, 85-year-old Madelyn Dunham, is very ill and Obama will take time off from the campaign trail to head to Hawaii to be with her later this week.
Obama spokesman Robert Gibbs told reporters on a flight to West Palm Beach, Fla., "Recently, his grandmother has become ill, and in the last few weeks, her health has deteriorated to the point where her situation is very serious. It is for that reason that Senator Obama has decided to change his schedule on Thursday and Friday so that he can see her and spend some time with her. He will be returning the the campaign trail on Saturday."
Gibbs called Dunham "one of the most important people" in Obama's life as she helped raise him along with her husband Stanley and her daughter, Obama's mother, Ann Dunham.
"Along with his mother and his grandfather, she raised him in Hawaii from the time he was born until the moment he left for college. As he said at the Democratic Convention, she poured everything she had into him," Gibbs said.
Obama visited his grandmother during his vacation in Hawaii in August; her condition had reportedly deterioriated this month and she was recently discharged from the hospital and is currently resting at her Honolulu home.