Grant Beltrami has lived to see 18 Thanksgivings, but never one as wrought with thankfulness as today’s.

After a three-month medical ordeal at Children’s Hospital of Wisconsin, Beltrami is finally responding to advanced bone marrow treatments needed to give him a future.

Stem cells donated by an anonymous German woman have taken root in Grant’s bone marrow, his mother Wendy reported this week. For the first time in a decade, Grant is beginning to produce healthy blood.

Grant isn’t totally out of the woods, but the signs are promising, Wendy Beltrami said.

“This is all pretty significant for us,” she said. “We’re feeling a lot of thanks for what is finally coming to an end.”

If Grant continues to make progress, he could transfer out of the hospital by Christmas and move into Ronald McDonald House with his parents, Wendy Beltrami said. He would continue treatment in Wisconsin to make sure his immune system does not reject his new marrow.

Grant could be back in his Napa home by late February, assuming there are no significant setbacks, she said. Grant is missing his senior year at Napa High School.

Today, the Beltramis, who are staying at a Ronald McDonald House for families of children with serious medical conditions, will share a turkey feast put on by Ronald McDonald supporters.

Grant has made such strong progress this past week that he will be issued a rare pass to leave the hospital’s isolation unit, his mother said.

If another child, befriended by the Beltrami family, cannot leave the hospital, he/she may join him for a Thanksgiving dinner, Wendy Beltrami said.

Waiting to see if Grant’s second bone marrow procedure will succeed has had dramatic ups and downs, including a stay in the pediatric intensive care unit and an alarming reaction to peanuts, his mom said.

Has Grant inherited a peanut allergy from the stem cell donor? The German woman will be tested to find out, Wendy Beltrami said.

Because his new marrow is beginning to work, doctors are giving Grant passes to leave the hospital for short periods. Outside his room, he wears a mask to ward off germs.

On Tuesday, Grant asked to visit his parents’ room at Ronald McDonald House and “take a real nap,” she said. This would be a nap beyond the sound of beeping medical equipment, without nurses and doctors interrupting to take his temperature and blood pressure, she said.

Ten years ago, Grant developed aplastic anemia, a rare bone marrow disease that diminished his ability to produce healthy blood. When his condition worsened last summer, his parents, Wendy and Joe, took Grant to Children’s Hospital of Wisconsin, a nationally recognized treatment center.

The first bone marrow transplant in September failed, requiring a second effort using the stem cells from the same German donor.

This time, Grant received a heavier dose of radiation and chemotherapy to be sure that all of his defective bone marrow was killed off, she said.

His marrow is now producing white blood cells that are 100 percent those of his German donor. Grant has regained the ability to fight off bacteria, although his white blood cells will need to learn to cope with viruses, his mother said.

If things go well, his new marrow soon will begin producing red blood cells to carry oxygen and platelets for clotting, she said.

Grant spends his time playing Scrabble, video games and bidding on $1 “Bags of Crap” on woot.com, his mother said.

He is still on three IVs as doctors deal with a variety of medical conditions, many of them brought on by the treatments to save his life, she said.

“Doctors refer to it as a chess game,” she said. “You make one move and counter it with another move.”

Napa residents have raised a substantial amount of money to support the parents while they are away from their jobs. Donations can be made to the Grant Beltrami Transplant Fund, care of the Bank of Napa, 2007 Redwood Road, Suite 101, Napa 94558.