Updated DEC 19, 2014 6:19p ET

Call it a Christmas miracle. That's pretty much the way Gordie Howe's family is describing his extraordinary recovery -- thanks to an experimental stem-cell treatment -- from a series of strokes that appeared to threaten the 86-year-old hockey legend's life only a few weeks ago.

"This is truly a Christmas miracle," said Dr. Murray Howe, a Toledo physician and one of Gordie's four children. "I would not have believed it if I hadn't seen it with my own eyes. "

Howe, gravely ill at the time, underwent the treatment on Dec. 8 in San Diego.

"As a family, we are thrilled that Dad's quality of life has greatly improved, and his progress has exceeded our greatest expectations," the Howe family said Friday in a news release in which it thanked a legion of fans praying for its father's recovery. "Once again, we cannot emphasize how much you have fueled Mr. Hockey's recovery, and we thank everyone for their continued prayers and support."

The neural stem cells were injected into the spinal canal on Day 1 and mesenchymal stem cells by intravenous infusion on Day 2, according to the release.

"His response was truly miraculous," the family said. "At the end of Day 1, he was walking with minimal effort for the first time since his stroke. By Day 2, he was conversing comfortably with family and staff at the clinic. On the third day, he walked to his seat on the plane under his own power."

Just five days later, Howe was walking unaided and even taking part in daily household chores, according to the release.

When tested, his ability to name items has gone from less than 25 percent before the procedure to 85 percent today, the release said.

"His physical therapists have been astonished," the family said. "Although his short-term memory, strength, endurance and coordination have plenty of room for improvement, we are hopeful that he will continue to improve in the months to come."

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Family: Experimental stem-cell treatment does wonders for Gordie Howe