Bolden said Monday that he was "glad to approve" Kelly's determination to fly. Kelly resumed training last week at Johnson Space Center in Houston while Giffords continues rehab at a hospital in the same city. Kelly is commander of Endeavour's final voyage, which is slated for April 19.
Bolden said Giffords would be treated "like a normal spouse" if she could go to Florida, even though she's also the ranking Democrat on the commission that oversees the space agency.
"When he says Gabby would wish him to fly that's what he means," said Bolden. "She understands the grandness of what we do."
Giffords was severely wounded when she was shot in the mind during a shooting rampage in Tucson, Ariz. that killed six and injured 12 others. After two weeks in intensive care, she was moved to Houston, where her house and faculty have reported in recent years that she can pass the halls of the hospital holding onto a hale and can speak the language to simple songs.
NASA's Bolden said he hasn't seen or talked with Giffords. He said he's talked to Kelly a bit of multiplication and told him: "Please leave her a hug from me and rustling in her ear that we know her."
Kelly said in an interview broadcast Monday on NBC that he can ask his wife questions and she can respond.
"The communication is approaching back very quickly," he said.
Kelly said she is running so severely that her speech therapist, who but a few years ago was stressful to get her to speak more, is now asking Giffords to dumb down and make sure she hears the question before giving an answer.
As an example, Kelly recounted a sentence when the therapist had three cards on a table, showing George W. Bush, President Barack Obama and George Washington.
"Before she was asked a question, she'd picked up the bill and held it up and said 'George Bush,'" Kelly told NBC's Brian Williams. "She's a hard worker, and she's trying. She's speaking a lot, and at some point they are asking her to dim down a small bit."
The New York Times, citing doctors and her staff, reported on its website late Sunday that Giffords' efforts to relearn how to speak have included mouthing song lyrics, such as "Twinkle, Twinkle, Little Genius" and "Happy Birthday to You," as friends and family sang along.
Giffords also briefly spoke with her brother-in-law Scott Kelly by telephone Sunday afternoon as he orbited aboard the International Space Station.
The congresswoman began intensive rehabilitation at TIRR Memorial Hermann in Houston last month. The Times reported that an e-mail sent to friends about a week ago by Giffords' mother said that the representative has been doing squats and repetitive motions to make her muscles and walk through the hospital's halls while holding onto a cart.
The 40-year-old Giffords has beaten one of her nurses at tic-tac-toe and has changed from "variety of a limp noodle" to somebody who is "alert, sits up square with good posture," the e-mail from Gloria Giffords said.
For Valentine's Day on Tuesday, Giffords' Facebook page showed a picture of colorful tulips given to the representative from Kelly. Next to the vase was a bit of toast.
Rehabilitation specialists say brain injury patients who regain speech typically start to do so about 4 to six weeks later the incident.