Former President George H.W. Bush has been hospitalized with a blood infection, one day after laying to rest Barbara, his beloved wife of 73 years.

Bush is suffering from an infection that spread to his blood, according to his spokesman, Jim McGrath.

The 41st president is "responding to treatments and appears to be recovering." He was admitted to Houston Methodist Hospital on Monday and is in critical condition, according to McGrath.

Bush attended the funeral of former first lady Barbara Bush Sunday, and joined dignitaries that included Bill Clinton, Hillary Clinton, Barack and Michelle Obama, son and 43rd president George W. Bush and current first lady Melania Trump.

Touched by thousands who came Friday to pay respect to his wife, the 93-year-old made a surprise visit to the church where her body lied in repose.

He arrived in a wheelchair with his daughter, Dorothy, and gazed up at the rose-covered metal casket carrying the remains of his wife.

A Secret Service agent turned Bush's wheelchair to face the pews of St. Martin's Episcopal Church. The former president began shaking the hands of a steady stream of mourners who filed by.

The elder Bush has suffered from ill health and uses a wheelchair for mobility after developing a form of Parkinson's disease. 

News agencies, including CNN, reported Monday night that Bush was suffering from sepsis, a serious infection that causes the immune system to attack one's body. It can be fatal, especially in the elderly. 

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