Former President George HW Bush is in the intensive care unit of a Texas hospital and is in "guarded condition," according to family spokesman Jim McGrath.
"The President is alert and conversing with medical staff, and is surrounded by family," McGrath said in a statement.
Bush was admitted to the intensive care unit on Sunday, he said.
More top news
Defence saving plans raise "serious doubts" over the Ministry of Defence's ability to pay for new equipment, including warships and planes.
One firefighter has been killed and more than 700 homes destroyed in the 404-square-mile Thomas Fire.
Theresa May has said there is "no place in our politics" for intimidation after Tory Brexit rebel MPs received death threats and abuse.