Former First Lady Barbara Bush has been taken to hospital suffering from early signs pneumonia.
Bush, 88, was admitted to the Methodist Hospital in Houston, Texas, on Monday.
The former First Lady is "in great spirits" and has already received visits from her husband and family, a statement from the office of former President George H.W. Bush said.
Barbara Bush had previously been hospitalised in 2010 after being diagnosed with a recurrence of Graves' disease, an autoimmune disorder affecting the thyroid.
She underwent a heart surgery in 2009 after being hospitalised suffering from abdominal pain resulting from a perforated ulcer in 2008, for which she underwent surgery.
The Bush matriarch served as First lady of the United States from 1989 to 1993 when George H.W. Bush was President. Her son, George W. Bush, served as the 43rd President of the United States from 2001 to 2009.