SACRAMENTO, Calif. -- A little boy diagnosed with cerebral palsy appears to have made a dramatic recovery after a transplant using his own umbilical cord-blood, his family says.

SLDIESHOW: Boy Makes Dramatic Recovery After Stem Cell Transplant

Dallas Hextell of Sacramento was diagnosed with cerebral palsy as a baby. According to his parents, he's now doing everything a typical toddler would do, thanks to a stem-cell transplant using his own blood.

Cynthia and Derak Hextell conceived in vitro after three years of trying. They said their son was a blessing -- but soon after his birth they knew something was wrong.

"He would cry for three hours straight like he was in pain," Cynthia said. "He couldn't really focus on things. When he started eating baby food he had chew-trouble, controlling his tongue."

A specialist eventually diagnosed Dallas as having brain damage that impaired his muscle control. Cynthia remembered they had preserved blood from his umbilical cord.

"There are a few places in the country that are offering services to store stem cells," said Dr. Steven Lindheim, a fertility specialist from San Diego. "People don't think about having something just in case something goes wrong," he said.

When Dallas was accepted to undergo a potentially life-changing procedure as part of a Duke University clinical trial, his parents jumped at the chance. Dallas's cord blood cells infused intravenously in less than an hour. His mother said just five days later, the child who had never uttered a word said, "Mama, mama."

"And of course, him and I started crying, and he grabbed the video camera," Cynthia said.

Once withdrawn, Dallas started waving, laughing and appeared more curious. Doctors said there's no way to prove Dallas' cord blood explains the change, but neither his mom nor dad said they need an explanation.

"I see hope. It just makes you believe in miracles," said Cynthia.

“[He’s changed] almost in every way you can imagine, just from five days afterwards saying ‘mama’ and waving,” she said. “We just feel like right now he really connects with you. It just seemed like a fog was over him before, like he just really wasn’t there. There was kind of, like a glaze in his eyes. Now, as you can see, you can’t get anything past him.”

"I think in the next five to 10 years it'll be standard of care just to have those stem cells in case they're needed," said Lindheim.