A trio of world leaders will spend Christmas Day in the hospital. Nelson Mandela, Margaret Thatcher and President George H.W. Bush will not be home for the holiday.
Bush was hospitalized Nov. 23 for treatment of a bronchitis-related cough.
Doctors say former he needs to "build up his energy" before he can be released from a Houston hospital.
Methodist Hospital spokesman George Kovacik said in an email statement Sunday that doctors are still optimistic that the 88-year-old Bush will make a full recovery.
He said doctors are being "extra cautious" with Bush's care.
The South Africa presidency says the anti-apartheid figure was admitted Dec. 8 to a hospital in Pretoria, the South African capital.
He was diagnosed with a lung infection and had a procedure to remove gallstones; officials have said Mandela is improving and is responding to treatment.
South African President Jacob Zuma says the whole country is behind Mandela and he is urging people to keep the former president in their thoughts on Christmas Day and throughout the holiday season.
Zuma describes Mandela, who was imprisoned under apartheid for 27 years, as an "ardent fighter."
Margaret Thatcher is recuperating at an unnamed hospital after the former British prime minister underwent a bladder operation.
Friend Tim Bell said that the 87-year-old Thatcher went to see her doctor after experiencing some discomfort and had what he described as a "small growth" removed.
He said late Friday the operation was over and had been "completely satisfactory." He said he couldn't go into detail as to the nature of the growth and declined to name the hospital, saying he did not want it to be inundated with calls.
Thatcher has been in uncertain health for several years, having suffered a series of small strokes more than a decade ago.
(Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)