McGrath said Bush is expected to remain under observation at the hospital for just a few more days, but is in "good spirits and resting comfortably".
Former President George H.W. Bush will remain hospitalized through the week, according to spokesman Jim McGrath.
George H.W. Bush, the oldest living president at 92, is suffering from chronic bronchitis after undergoing treatment for pneumonia.
The hospitalization is the second this year for Bush.
"This means his airway has a constant, low-level inflammation that can aggravate the symptoms of pneumonia".
Bush got a visit from his son, President George W. Bush, last week. No father has ever been more blessed, or prouder'.
In January, Bush was sent to this hospital with an acute respiratory problem. He and his wife, Barbara Bush, are scheduled to travel to ME soon, and doctors want to "ensure (he has) a fully clean bill of health", McGrath said.
Bush, who served in the White House from 1989 to 1993, spent more than two weeks at Houston Methodist in January, much of it in the intensive care unit, during a bout of pneumonia.
The letter was written before he was admitted to hospital with pneumonia.