Will be updated.
Updated 12:25 p.m. with more information about Kirk's family's reactions, well-wishes from Ill. Gov. Quinn.
Updated at 1:35 with statements from Sen. Dick Durbin and more information from the doctors.
Relatives of U.S. Sen. Mark Kirk say they're very encouraged by doctors' prognosis after the Illinois Republican underwent surgery following a stroke.
A Kirk staffer read a statement from the family Monday at a news conference in Chicago. The statement says family members are thankful for the good medical care the 52-year-old senator has received. They say they're also grateful for the support of friends and family.
Family members say Kirk has always been resilient and they're hopeful he'll recover.
Dr. Richard Fessler, a neurologist at Northwestern University Memorial Hospital in Chicago, says surgeons removed a portion of the senator's skull to relieve pressure on his brain. Fessler says Kirk is in intensive care, but doctors are happy with his status, and that the Republican appeared to recognize those around him and responded to commands. Fessler says Kirk suffered a stroke on the right side of his brain which controls movement of his left arm and left leg.
A spokesperson for Sen. Mark Kirk says the Illinois Republican has suffered a stroke and has undergone surgery.
The 52-year-old Kirk checked himself into Lake Forest Hospital in Illinois over the weekend. He was later transferred to Northwestern Memorial Hospital in Chicago, where tests showed that he had suffered a stroke.
He underwent surgery Sunday to relieve swelling around his brain.
A statement from Kirk's office said the surgery was successful and that doctors are "very confident" in his recovery based on his age and health.
Kirk was elected to the Senate in 2010, winning the seat formerly held by President Barack Obama.
The hospital plans a news conference this morning.
Missouri Republican senator Roy Blunt offered his well-wishes to Kirk in a statement:
“Mark is one of my closest friends in the Senate and he's been a valued colleague of mine for many years, including as one of my deputies when I was the Whip in the House. He’s a strong advocate for his views, he works hard, and he’s a great neighbor. Missouri, along with Illinois and the rest of the nation, benefits greatly from Mark Kirk’s leadership. I’m encouraged by his doctor’s comments and wish him a very speedy recovery.”
As did Ill. Gov. Pat Quinn:
“Our heartfelt thoughts and prayers go out to the senator and his family as we wish him a swift and strong recovery. We can all take comfort knowing that as a Navy commander, Sen. Kirk knows how to fight and he will fight through this to return to his work on behalf of the people of Illinois as quickly as possible.”
Democratic Sen. Dick Durbin also offered well-wishes to his colleague:
"I was stunned to learn that Mark suffered a stroke. He is young and in good physical condition and I have no doubt he will make a speedy recovery. I have reached out to his staff and offered to do anything I can to help with his Senate duties. Loretta and I will keep Mark and his family in our prayers."