Former US President George H.W. Bush has been hospitalized in Houston since the weekend after he experienced a shortness of breath, a family spokesman said on Wednesday.

Bush, 92, the oldest living former American president, has been at the Houston Methodist Hospital since Saturday and ‘has responded very well to treatments,’ spokesman Jim McGrath said in an email to Reuters.

‘Doctors and everyone are very pleased, and we hope to have him out soon,’ McGrath wrote.

Bush is the father of former President George W. Bush and former Florida Governor Jeb Bush, who sought the 2016 Republican presidential nomination.

The elder Bush, a Republican like his sons, served as vice president during Ronald Reagan’s two White House terms before being elected president in 1988. He served four years in the White House.

Bush has used a wheelchair in his later years and was hospitalized twice in 2014 — once for seven weeks with pneumonia and again for breathing difficulties. In July 2015 he broke a bone in his neck in a fall at the family home in Maine.

Bush’s public appearances have been rare since he entered his 90s. In October 2015, Bush, sitting his wheelchair, wearing a brace on his neck and clad in a Houston Astros jersey, tossed out the first pitch at the team’s playoff game against the Kansas City Royals.

In 2016, he marked the 75th anniversary of Japan’s attack on Pearl Harbor by attending a ceremony at his library at Texas A&M University where Bob Dole, the former Republican Senator from Kansas, was presented with an award for public service.