Former President George H.W. Bush remained hospitalized on Friday but was showing signs of improvement, a family spokesman said.
"President Bush remains in the intensive care unit at Methodist Hospital, where he continues to improve," spokesman Jim McGrath said in a prepared statement. "The president is alert and, as always, in good spirits -- and his exchanges with doctors and nurses now include singing."
Bush, 88, was admitted to the Houston hospital on Nov. 23 suffering from a bronchial cough. While the cough has lessened, McGrath said earlier this week, a persistent fever prompted doctors to move him into the intensive care unit on Sunday.
"The Bushes thank everyone for their prayers and good wishes and, like their doctors, are cautiously optimistic that the current course of treatment will be effective," McGrath said Friday.
The 41st president and his wife, Barbara, live in Houston during the winter. When it was clear Bush's health would keep him hospitalized over the holidays, McGrath said doctors were simply being cautious. "Given his current condition, doctors just want to hang on to him," McGrath said.
Bush, a naval aviator in World War II who was shot down over the Pacific, achieved notoriety in retirement for skydiving on at least three of his birthdays since leaving the White House in 1992.
Throughout his hospital stay, he has been surrounded by family, including visits from his son, Neil, and Neil's wife, Maria, and a grandson, as well as sons George W. Bush, the 43rd president, and Jeb Bush, the former governor of Florida.
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